blank
1U Server
Intel CPU
AMD CPU
2U Server
Intel CPU
AMD CPU
3U Server
Intel CPU
AMD CPU
4U Server
Intel CPU
AMD CPU
5U+ Server
Intel CPU
AMD CPU
Tower Server
Intel CPU
AMD CPU
Blade Server
Intel CPU
AMD CPU
Data Storage
Intel CPU
AMD CPU
GPU Server
Intel CPU
AMD CPU
H-Density Server
Intel CPU
AMD CPU
Virtualization
Intel CPU
AMD CPU
Quiet Workstation
Intel CPU
AMD CPU
AMD Server
Intel Server
Component
Chassis
Controller Cards
Cooling / Fan
Hard Drive
Memory
Motherboard
Network Card
Processor
PC Barebone
Power Supply / UPS
Software
Server
Video Card
Peripheral
Accessories
Cable / Adapter
CD/ DVD /Floppy
Duplicator
Flash Memory
IO Card
Monitor
Mouse / Keyboard
Multimedia
Networking
Notebook
Printer
Service
To Modify your order quantity:
Enter new quantity in New Qty field and press Update Qty.
To Remove a product from your cart:
Set the quantity to zero.
To process the order:
Press Check Out button.
New Qty.
ITEM
Atacom Part No.
PRICE
QTY.
AMOUNT
Gigabyte Motherboard Z370 HD3 Intel Z370 Chipset Gen 8 Core i7/i5/i3 Socket LGA1151 DDR4, GBLAN, 6 x SATA3/M.2, HDMI/DVI-D, PCIe 3.0, USB 3.1, ATX Retail
MB01_GIGA_Z3_62
$269.95
1
$269.95
Plantronics 83545-01 W710 SAVI 3IN1 MONOAURAL OVER THE HEAD HEADSET W/ MIC UC
PHON_PLAT_83_60
$359.95
1
$359.95
Viewsonic VX2252MH 21.5 Inch LCD Full HD 2ms 50000000:1 1080P VGA, DVI, HDMI Monitor (Retail)
ML21_VIEW_VX_11
$174.95
1
$174.95
ASRock Motherboard B450M PRO4 AMD Ryzen B450 AM4 Max.64GB DDR4 PCI Express Micro ATX Windows10 Retail
MBM4_ASRK_B4_59
$139.95
1
$139.95
IEI, 15 inch, 2048 x 2048, 5-wire Touch Screen, T-R150G-USB, Serial RS-232
IDLT_IEIX_15_U3
$230.00
1
$230.00
IEI 33Z00-000031-RS DVI-I To VGA Adapter, Cable Accessory
IAAD_IEIX_DI_VA
$49.95
1
$49.95
WD/HGST WUS721010AL5204 3.5 Inch 10TB SAS 12Gb/s 7.2K RPM 256M 0B42258 512e SE (Vela-AX)
HDSS_HITA_10_17
$273.95
1
$273.95
IEI Panel PC-5150A-G41-E15/R/1G-R10 15INCH 350 cd/mē XGA Panel PC with POperating System-G41 Celeron Dual Core E1500 2.2GHz CPU 1GB DDR3 RAM x22AP touch screen
ISPP_IEIX_DC_01
$1375.00
1
$1375.00
IEI IEM-LX-800-R11 ETX CPU Module AMD LX800 500MHz processor VGA/LVDS/TTL LAN & Audio
IMB3_IEIX_AG_01
$285.95
1
$285.95
IEI WAFER-PV-N4552-R10 3.5 Inch Embedded Single Board Computer WAFER w/ On-Board Atom N455 1.66GHz 512KB Single Core, DDR3 SO-DIMM, VGA, LVDS, 2x GBLAN
IMB3_IEIX_AP_09
$399.95
1
$399.95
EPSON T027201 ORIGINAL INKJET CARTRIDGE (5-COLOR)
PRIN_EPSO_R7_01
$35.95
1
$35.95
EVGA Video Card 10G-P5-3897-KR GeForce RTX 3080 FTW3 ULTRA GAMING 10GB GDDR6X Retail
VIDR_EVGA_30_80
$1038.95
1
$1038.95
Portwell WEBS-1053 (1460) Intel Atom E3815 (1.46 GHz) Nano-ITX MAX 4GB Display Port, Dual Gigabit Ethernet, USB 3.0 and SATA SSD Nano-ITX System
IMBN_PORT_AE_07
$518.00
2
$1036.00
Supermicro SYS-5038K-I-NF3,Mid-Tower Server Barebone, Single Intel Xeon (Phi 7230) Scalable Socket P(LGA3647) CPU,C612 chipset,DDR4,6 x 3.5in/4 x 2.5in Bay,2xGBLAN,IPMI,SATA,PCI-E,VGA,USB Per Node,750W Multi-Purpose PSU: K1SPE & CSE-GS5A-753B
SYIT_SUPE_50_6F
$1774.95
1
$1774.95
Vantec 8TB NexStar HX4 Quad 3.5 Inch SATA to USB 3.0 & eSATA w/ RAID External Hard Drive: NST-640S3R-BK-8TB
HDIU_VANT_S4_08
$799.95
1
$799.95
Kingston Memory HX432C18FWK2/32 32GB 3200MHz DDR4 CL18 DIMM Kit of 2 HyperX FURY White Retail
MED4_KING_32_4W
$328.99
1
$328.99
Kingston ME KSM26RD4 64MFR 64GB 2666MT s DDR4 ECC Reg CL19 DIMM 2Rx4 Micron F
MEE4_KING_2A_4L
$290.95
1
$290.95
Supermicro SYS-1027TR-TQF 1U Rackmount Server Barebone VMWare Certified 2 Node, C602J, Dual XEON E5-2600 LGA2011, 4x 2.5 Hot-Swap HDD, DDR3, 2x GBLAN, IPMI, SATA 3G, Infiniband, 1280W PSU w/ X9DRT-IBQF, CSE-809BTQ-1K28B
SYI1_SUPE_10_26
$2926.95
1
$2926.95
IEI ACT-457A-1250/T-R/POE/-R10 5.7 Inch 640x480, 300:1 Touchscreen, Alchemy AU1250 500Mhz,2x COM, PoE LAN, 2x USB 2.0, SD Slot, All-In-One Access Control Terminal
ISCT_IEIX_05_73
$660.00
1
$660.00
IEI ACT-412A-N270/R/1G-R23 12.1 Inch 1024x768, 700:1 Touchscreen, Intel Atom N270 1.6GHz 945GSE w/ 1GB RAM, Wi-Fi, 2x COM, 2x GBLAN, 3x USB 2.0, 1x eSATA, CF Slot, 1x 2.5 HDD, All-In-One Access Control Terminal
ISCT_IEIX_AD_A5
$927.95
1
$927.95
Accell ProUltra HDMI-A/HDMI-A Cable, v1.3 - 16ft (5m) B077C-016B-40
CABV_ACCE_HP_17
$30.95
1
$30.95
IEI AFL-19i-HM55i5-52/R/2G-R21 19 in 350 cd/sq.m SXGA panel PC with IntelŪ Core i5-520M 2.4G CPU,2GB DDR3 RAM,802.11 b/g/n wireless module,touch screen,R21
ISPP_IEIX_MI_1W
$1999.95
1
$1999.95
TRIPP LITE 5M (16FT) 10GB DUPLEX MMF 50/125 OM3 LSZH PATCH CABLE (Mini-LC/LC) - AQUA: N836-05M
CABN_TRIP_N8_33
$80.95
1
$80.95
IBase MI980VF-4400E ITX Motherboard i5-4400E+FAN QM87 V/2 GL 6COM SATA RAID PCIe+mPCIe vPRO
IMBM_IBAS_MI_73
$899.95
1
$899.95
Intel 3D XPoint DC P4801X 200G PCIe3.0x4 60DWPD M.2 22x110 ( SSDPEL1K200GA )
IFMS_INTE_02_19
$573.95
1
$573.95
Lian-Li Case Lancool III RGB White Full Tower 4mm tempered glass 3x140mm ARGB Fans White Retail
CASS_LILI_2A_0B
$170.95
1
$170.95
ASUS VCX DUAL-RTX3060-O12G-V2 GeForce RTX 3060 12GB GDDR6 192Bit PCIE Retail
VIDR_ASUS_2A_1N
$475.95
1
$475.95
Samsung Solid State Drive MZ-76Q4T0B/AM SSD 860 QVO 2.5 inch SATA III 4TB Retail
SSDX_SAMS_4T_11
$514.95
1
$514.95
Seagate Hard Drive ST600MP0146 600GB SAS 15K 128MB 12Gb/s 2.5 Inch SED 4Kn/512E Bare
HDS2_SEAG_A6_01
$247.95
1
$247.95
Seagate Hard Drive ST8000NM0135 8TB 7200RPM SAS 256MB 6Gb/s 3.5 inch 512e Retail
HDSS_SEAG_8T_11
$337.95
1
$337.95
NVIDIA Video Crad 900-2G402-0010-000 Tesla M60 16GB DDR5 PCI Express3 Passive Right-to-Left Airflow Brown Box
VIDR_NVID_TE_63
$5358.95
1
$5358.95
SUPERMICRO PWS-561-1H 1U 560W W/ STANDARD HARMESS OUTPUT
POWS_SUPE_PW_07
$165.95
1
$165.95
Kingston KVR16N11S8H/4 4GB PC3-12800 DDR3-1600MHz Non-ECC CL11 Memory RAM
MED3_KING_12_DD
$52.95
1
$52.95
Supermicro X11SCZ-Q-O uATX Motherboard Intel Q370 Chipset, Single Gen 8 Core i7/i5/i3 Socket H4 (LGA1151) CPU, DDR4, 2 x GbLAN, 5 x SATA3/M.2, PCIe 3.0, USB 3.1, 2 x DisplayPort/DVI-I: MBD-X11SCZ-Q-O
MB01_SUPE_Q3_16
$342.95
1
$342.95
Seagate ST6000NM0175 Enterprise Capacity 6TB 3.5in 7200RPM 256MB SATA3 6Gb/s SED 512E Hard Drive
HDSA_SEAG_6T_33
$191.40
1
$191.40
Asus Motherboard TUF B360-PRO GAMING WI-FI Intel B360 Chipset Gen 8 Core i7/i5/i3 Socket LGA1151 DDR4, GBLAN, Wi-Fi/Bluetooth, 6 x SATA3/2 x M.2, HDMI/VGA, PCIe 3.0, USB 3.1, ATX Retail
MB01_ASUS_B3_6A
$216.95
1
$216.95
Kingston Memory KVR26S19D8/16 16GB 2666MHz DDR4 Non-ECC CL19 SODIMM 2Rx8 Retail
MEN4_KING_16_61
$75.95
1
$75.95
Innodisk D1ST-32GJ13C1 1.8 Inch 64GB FiDSATAII 10000 Flash in Disk, 160 Read / 140 Write
IFCD_INNO_D1_24
$475.95
1
$475.95
Kingston DTVP/32GB 32GB DataTraveler Vault Privacy Edition USB 2.0 up to 24MB/s Read, 10MB/s Write Flash Drive w/ 256-bit Encryption
MEUS_KING_32_11
$123.95
1
$123.95
Kingston DTM30/32GB 32GB USB 3.0 Flash USB 3.0 DataTraveler Mini
MEUS_KING_32_M3
$25.95
1
$25.95
Lenovo Business Topload Case (43R2476)
NOAC_LENO_CS_76
$69.95
1
$69.95
ASUS MB ROG STRIX B560-A GAM WIFI B560 LGA1200 Max.128GB DDR4 HDMI DP W10 ATX ( ROGSTRIXB560-AGAMWIFI )
MB02_ASUS_2A_05
$187.95
1
$187.95
IEI SPCIE-C2160-DVI-R10 Full-size PICMG 1.3 CPU Card
IMP3_IEIX_XS_07
$450.00
1
$450.00
Bytecc USB 3.0 2-Port ExpressCard/34 Controller Card BTU3-EC200
CONI_ATAC_U3_E2
$29.95
1
$29.95
Kingston HX424C15FBK2/8 8GB 2400MHz DDR4 CL15 DIMM (Kit of 2) HyperX FURY Black Retail
MED4_KING_08_43
$199.95
1
$199.95
Asus Motherboard STRIX Z370-H GAMING Intel Z370 Chipset Gen 8 Core i7/i5/i3 Socket LGA1151 DDR4, GBLAN, 6 x SATA3/2 x M.2, HDMI/DVI, PCIe 3.0, USB 3.1, ATX Retail
MB01_ASUS_Z3_79
$199.95
1
$199.95
Supermicro SYS-6017R-73THDP+ 1U Rackmount Intel XEON E5-2600 Intel C602 LGA2011 SuperServer DDR3, 2x 10GBase-T, 1x PCI-E X4, 12x 3.5 HDD, SAS3, SATA 6G, IPMI, RAID, VGA, 650W PSU w/ X9DRFF-7TG+, CSE-816LT-655B: SYS-6017R-73THDP+
SYI1_SUPE_60_RI
$1654.95
1
$1654.95
Seagate HDD ST2000VX005 2TB SATA 6Gb/s 64MB 3.5 inch Surveillance HDD Bare
HDSA_SEAG_3T_1L
$129.95
1
$129.95
Supermicro SYS-5028TK-HTR-NF5,2U Rackmount Server Barebone (4 Nodes), Single Intel Xeon (Phi 7250) Scalable Socket P(LGA3647) CPU,C612 chipset,DDR4,3 x 3.5in Bay,2xGBLAN,IPMI,SATA,PCI-E,VGA,USB Per Node,2000W Redundant PSU:K1SPi & CSE-827HQ+-R2K04BP2
SYI2_SUPE_25_0J
$13179.95
1
$13179.95
Intel SSD SSDPEKNW010T8X1 660p M.2 80mm 1TB PCI-express 3.0x4 3D2 QLC Single Pack Retail
IFMS_INTE_10_07
$105.95
1
$105.95
Intel CPU CM8068404224102 Xeon E-2288G 16M 3.70 GHz FC-LGA14A/ LGA1151 Tray Bare
CP46_INTE_E2_2B
$582.95
1
$582.95
PNY Video Card VCQP1000V2-PB NVIDIA Quadro P1000 v2 4GB GDDR5 Retail
VIDR_PNYX_40_01
$368.95
1
$368.95
Kingston FA-LYD-25P Lanyard Accessory
MEUS_KING_FA_12
$32.95
1
$32.95
Kensington K62348 CONTOUR ROLLER TELESCOPING HANDLE BLACK/SILVER
NOAC_KENS_62_12
$108.95
1
$108.95
Supermicro X9SCAA-L-O mini-ITX Intel Atom N2800 Intel NM10 Motherboard DDR3, 2x GBLAN, LVDS, VGA, DOM: MBD-X9SCAA-L-O
MBMI_SUPE_NM_12
$172.70
1
$172.70
Seagate SSD XS7680SE70024 7.68T Nytro3331 SAS 2.5 inch SED FIPS Retail
SSDS_SEAG_7T_17
$2182.95
1
$2182.95
IEI TANK-760-HM86i-C/4G-R10 Fanless embedded system , Intel Celeron dual-core 2000E 2.2GHz, TDP 37W, 2GB DDR3 pre-installed memory , VGA/HDMI/Displayport, iRIS-2400 optional, 9-36V DC, RoHs, R10
ISFB_IEIX_MI_76
$1027.20
1
$1027.20
ASUS RT RT-AX82U AX5400 Dual-band WiFi6 Gaming Router Mesh WiFi support Retail
NETR_ASUS_2A_05
$239.95
1
$239.95
Kingston ME KSM26RS4 32HAI 32G 2666MHz DR4 ECC Reg CL19 DIMM 1Rx4 Hynix A IDT
MEE4_KING_2A_19
$184.95
1
$184.95
Kingston SSD SEDC450R 7680G 7.68TB DC450R 2.5 SATA Retail
SSDX_KING_07_61
$1214.95
1
$1214.95
Intel CPU Core i9-9920X Boxed 19.25MB Cache 3.5GHz LGA2066 12Cores/24Threads Retail BX80673I99920X
CP06_INTE_I9_92
$1093.95
1
$1093.95
CHENBRO RM RM41300-R875F2 4U 3x5.25inch Extended ATX PS/2 Single Retail
CASR_CHEN_11_5L
$619.95
1
$619.95
Fractal Design Case FD-CA-DEF-R6C-WT-TGC Define R6 USB-C White TG EATX/ATX/mATX Mid Tower Retail
CASX_FRAC_11_11
$185.95
1
$185.95
IEI AFLFP-408A-B-R10 8.4INCH Faceplate for AFL-408A series Black color
IAMO_IEIX_AF_05
$140.00
1
$140.00
Chenbro Rackmount RM41300-R875F1 4U 3x5.25 875W 1+1 Redundant 7Slot Extended ATX Retail
CASR_CHEN_11_67
$644.95
1
$644.95
EVGA Power Supply 210-GQ-0750-V1 750 GQ Gold 100-240 VAC +12 750W Retail
POWS_EVGA_75_03
$188.95
1
$188.95
Supermicro SYS-1029UX-LL2-S16, 1U Rackmount Server Barebone, Dual Intel Xeon Scalable Socket P(LGA3647) CPU, C621 chipset, DDR4, 8 x 2.5in SAS3/ 2 x 2.5in NVMe, 4 x GbLAN, IPMI, PCI-E, VGA, USB, 750W Redundant PSU: X11DPU-XLL & CSE-119UTS-R751P-T
SYI1_SUPE_1D_3F
$14649.95
1
$14649.95
ASUS MB ROG STRIX B550-I GAMING B550 AMD Ryzen AM4 max64GB DDR4 MiniITX Retail
MBM4_ASUS_B5_51
$327.95
1
$327.95
Asus Network PCE-AC88 AC3100 Dual-Band Wireless PCI Express Adapter 802.11ac Retail
NETW_ASUS_AC_13
$114.95
1
$114.95
Supermicro X11SSQ-O microATX Motherboard, Intel Q170 Express Chipset, Single 6th Gen Core i7/i5/i3 Socket H4 (LGA1151), DDR4, 2 x GBLAN, SATA3, PCI-E, DOM, DVI-D/DisplayPort/HDMI, USB: MBD-X11SSQ-O
MB01_SUPE_Q1_72
$253.95
1
$253.95
Lian-Li Case LANCOOL II-W Tempered Glass 3x3.5/2x2.5 E-ATX/ATX/M-ATX/ITX White Tower Retail
CASX_LILI_11_19
$91.95
1
$91.95
Athena Case RM-1U100DD308 1U Rackmount Chassis 300W Power Supply RM-1U100DD + AP-FATX30P8 Brown Box
CASR_ATHE_11_11
$355.95
1
$355.95
Supermicro SYS-6018R-TDW C612 Dual Xeon E5-2600 v3 Socket R3 (LGA2011) 1U Rackmount Server Barebone , DDR4, 4 x 3.5in Drive Bays, GBLAN, IPMI, SATA3, PCI-E, USB, 2 x DOM Ports, 600W Multi-Output Power Supply, w/ X10DDW-i
SYI1_SUPE_1D_67
$1075.95
1
$1075.95
Corsair Power Supply CP-9020123-NA CX750 750 Watts 80+ BRONZE ATX Retail
POWS_CORS_11_23
$102.95
1
$102.95
Supermicro A1SRM-2758F-O Intel Atom C2758 8-core microATX Motherboard w/ SATA 6G, 4x GBLAN, IPMI, VGA, 1x PCI-E x8, 1x PCI-E x4: MBD-A1SRM-2758F-O
MBMI_SUPE_A1_11
$384.95
1
$384.95
Intel Xeon W-2125 W Series, 4.0GHz 4Core/8Thread 8.25MB Cache, Socket R4(LGA2066) 14nm, 120W Processor, Tray: CD8067303533303
CX26_INTE_21_08
$499.95
1
$499.95
Supermicro SC846XE1C-R1K23B E-ATX 4U Rackmount Chassis, 24x 3.5 Hot-Swap HDD Bays w/SES2, Single SAS3 Expander Backplane,1200W Redundant Power Supply (Black): CSE-846XE1C-R1K23B
CASR_SUPE_47_35
$2306.95
1
$2306.95
Advantech 12.1 Inch 1024x768 5-wire Resistive Touch Display Kit XGA IDK-121R-42XGA1 LVDS 18/24 bits LED 500 Nits Backlight Life 50K
IDLT_ADVA_A2_06
$365.95
1
$365.95
Supermicro SYS-5018D-MTRF 1U Rackmount Intel XEON 4th Gen Intel C224 LGA2011 SuperServer DDR3, 2x GBLAN, PCI-E X8, 4x 3.5 Hot-Swap HDD, SATA 6G, RAID, IPMI, VGA, 400W PSU, DOM, USB 3.0 w/ X10SLM-F, CSE-813MTQ-R400CB: SYS-5018D-MTRF
SYI1_SUPE_50_1U
$991.95
1
$991.95
IEI,TANK-GM45A-R10/P8600/2GB,Intel GM45 + ICH9M,Extended Temperature Fanless Embedded System,Intel Core 2 Duo P8600 2.4 GHz 3MB L2 cache ,2 GB DDR2 SODIMM Memory Pre-installed, 1 x VGA,2 x Intel GbE
ISFB_IEIX_MC_03
$1102.95
1
$1102.95
Intel Xeon E7-8860 v3 Haswell 2.2GH/z 40MB 16-Core/32-Threads 9.6GT/s 140W LGA2011 Tray/OEM Server CPU Processor: CM8064502017900
CP2M_INTE_E7_H1
$4229.95
1
$4229.95
ACS ACR38U-N1 PocketMate USB Smart Card Reader
MERD_ATAC_AC_19
$23.95
1
$23.95
Advantech AIMB-552G2-00A1E Intel 915GMLE microATX Motherboard w/ Optional Intel Pentium M/Celeron M Socket 479 , 2GB DDR2-533, VGA, LVDS, DVI, 2x GBLAN
IMBI_ADVA_MM_03
$320.00
1
$320.00
QNAP TS-1273U-RP-8G-US 12-Bay 2U Rackmount Diskless NAS System w/AMD RX-421ND CPU and 8GB RAM
NASX_QNAP_TS_73
$2563.95
1
$2563.95
iBase SBC-IB965RF (v1.3) LGA1155 Q77 full-size CPU card with VGA, DVI-D, 24-bit LVDS, dual gigabit LAN, iSMART, TPM 1.2, RAID
IMP3_IBAS_DI_37
$344.40
1
$344.40
Allied Telesis AT-x230-18GP 16 POE+ Port Layer 3 Manageable Gigabit Ethernet Switch
NETS_ALLD_23_04
$1729.95
1
$1729.95
Promise P2R6HD12US PEGASUS2 R6 12TB RAID TB2 SOLUTION WITH 1M TB2 CABLE
ERCA_PROM_P2_12
$2472.95
1
$2472.95
TYAN S7070A2NR-B Server Motherboard Dual Intel XEON E5-2600 v3 Socket R3(LGA2011) CPU, Intel C612 chipset DDR4 SATA III PCI-E (2) GBLAN IPMI Realtek Audio SSI CEB
MB23_TYAN_S7_21
$327.95
1
$327.95
HGST HD 0F29590 12TB 3.5 26.1MM 256MB 7200RPM SATA ULTRA 512E ISE P3 DC HC520
HDSA_HITA_12_01
$527.95
1
$527.95
ARLOTTO 208DBG DUAL SPEEDS 10/100MB 8 PORTS DESKTOP HUB W/BRIDGE & ...
NETH_ARLO_08_03
$164.95
1
$164.95
StarTech Controller Card PEXM2SAT3422 2xM.2 NGFF SSD RAID Controller Card with 2xSATA3 Ports Retail
CONA_STAR_12_15
$179.95
1
$179.95
Kingston Memory HX432C16PB3K4/32 32GB 3200MHz DDR4 CL16 DIMM HyperX Preda
MEE4_KING_32_67
$215.95
1
$215.95
Intel SSD SSDPELKX020T801 DC P4511 2.0TB PCIe 3.1x4 3D2 TLC Single Brown Box
SSPC_INTE_20_03
$642.95
1
$642.95
Jetway HCWIFI097AN-F 802.11 b/g/n + Bluetooth 4.0 class II Atheros AR9485 with AR3012 Chipset Half-size Mini-PCIE card includes full-size bracket 1 x pigtail 1 x 2dB SMA Antenna
NETA_JETA_WF_01
$35.00
1
$35.00
ASUS MN VP32UQ 31.5 4K UHD 3840x2160 4ms 1000:1 DP HDMI Retail
MN30_ASUS_2A_1L
$420.95
1
$420.95
Subtotal:
$87770.59
Coupon Code:
To know Shipping/Handling Charge before Submit Order:
Please input ZIP CODE and press Preview Button.
Zip Code:
© 1998 ATACOM, Inc. All rights reserved. Published by ATACOM, Inc. All product names throughout this catalog are trademarks of their respective holders.