Gong Base Metal (Cast Iron) for American Clocks with Mounting Screw

(Packet of 10 pcs) A) 0.80 (2.10 x 2.20mm) D) 1.00 (3.30 x 3.40mm) B) 0.90 (2.50 x 2.60mm) E) 1.10 (3.70 x 3.80mm) C) 0.90 (2.90 x 3.00mm) F) 1.10 (4.10 x 4.20mm)

Key sizes: 5-6, 7-8 and 10-12. Put chuck in the handle and slowly release the mainspring.