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Front view of FANUC A20B-3900-0042 memory module PCB

FANUC A20B-3900-0042 SRAM Memory Module 4MB

In stock
$225.00 USD
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All parts are covered by REACO CNC warranty

All parts are covered by REACO CNC warranty

Every part is carefully inspected and tested for reliability。

All parts tested under load

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More than 150,000 parts in stock & ready for delivery

More than 100,000 parts in stock & ready for delivery

FANUC A20B-3900-0042 SRAM Memory Module 4MB – Tested

Brand FANUC
Model A20B-3900-0042
Handing time within 1-2 working days
Shipping Method DHL/UPS/FedEx
Estimated Delivery Time (via DHL)

Asia: 1-3 business days

Europe: 2-4 business days

North America: 2-4 business days

South America:  3-6 business days

Middle East & Africa: 3-6 business days

Oceania: 2-5 business days

Warranty NEW/Refurbished: 1-Year warranty
Used(90% New): 3-Month warranty
Category PCBs
Parameter Description

A20B39000042
DISCONTINUED BY MANUFACTURER
MEMORY MODULE
S-RAM
4MB

Service Test video will be sent before delivery
Packing Cartons

 

The A20B-3900-0042 PCB is a SRAM memory module used in FANUC CNC systems, featuring 4MB storage capacity.

It provides:

  • Reliable system memory storage
  • Stable data retention
  • Support for CNC program execution

This module is discontinued by the manufacturer, making it a critical replacement for legacy systems.

  • Fully tested before shipment
  • In stock and ready to ship
  • Fast global shipping available

Product Details

Part Number: A20B-3900-0042
Type: SRAM Memory Module
Memory: 4MB
Function: Data Storage / Retention
Application: CNC Systems
Status: Discontinued

Manufacturer: FANUC


Applications

FANUC CNC systems
Program storage and backup
Industrial automation
System repair and maintenance


Sales & Support

Tested memory modules
Fast worldwide shipping
Technical support available

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