You are buying the replacement Panasonic turntable counterweight that you see in the photos. It weighs around 105 grams. The inside diameter is JUST a hair over 10mm.
This particular tonearm weight was taken from a Panasonic model that had a faux wood base. I can't remember the exact model, sorry. I cannot answer questions about compatibility, sorry. Some nicks around the edge.
Super condition. Very clean with no damage or issues to worry about.
Ships quickly and carefully. It might actually fit some Technics models, too!