For sale is an Intel A80387DX-20 math coprocessor / floating point unit for vintage 386DX PC systems.

This is the 20MHz version of Intel’s 80387DX FPU, intended for compatible 386DX motherboards with a matching 80387DX coprocessor socket.

Please confirm compatibility with your specific motherboard before purchase. This is the DX version of the 80387 coprocessor and is not the same as the smaller 80387SX version used with 386SX systems.

Fast and careful shipping from Tokyo, Japan.Please be aware of any customs import duties or taxes in your country.
🇺🇸 US buyers: shipments are sent DDP (Delivered Duty Paid), which means there are no duty fees on delivery, as duties are included in the shipping rate.
Please also note that customs delays may occur, particularly within the EU.
This is vintage hardware/software for vintage computers. Use of this item requires era-appropriate knowledge and compatible hardware/software. Please carefully verify your intended use and compatibility before purchasing. I am happy to answer reasonable questions, but compatibility with every system or configuration cannot be guaranteed, and step-by-step installation support is not provided. Issues arising from incorrect installation, modification, or incompatible use are outside the seller’s responsibility.
I usually ship within 24 hours. If shipping falls on a Saturday in Japan, dispatch may occur the following Monday.