Check the listing for details. Cross Peen Metal Working Hammer- Marked 200. Condition: Used. Listed at 19.98 USD. The Cross Peen Metal Working Hammer marked with the number 200 is a specialized tool used in blacksmithing and metalworking. This type of hammer is designed with a cross-peen head, which is ideal for shaping and directing metal in a precise manner. The marked number 200 indicates a specific weight or size, making it a unique and specific addition to any collection of tools or for a blacksmith's workshop.