The Omron CS1W-KS001 is a replacement key sheet for the CS1 Series PLCs, specifically the Japanese PRO27 layout. It's the membrane overlay that goes over the programming console keypad — the part you swap when the letters wear off or a key gets sticky out here in the grease.
Bulk packaged, so it ships loose in a bag — no individual retail box. Designed for the CS1 Series programming console; if you're swapping one on a line that's down, verify the console model matches the PRO27 Japanese layout before you pull the old one off.