This listing is for 2 Jacobs Brand K-32 Chuck Keys. These T-handle keys have a 1/4" pilot (.248") (6.35mm) and 10 teeth. They fit the following Jacobs chucks 11N, 32, 32B, 33, 3326A, 33B, 33BA, 33F as well as a lot more. These are new unused Original Jacobs Brand Keys. They should fit any brand chuck with a 1/4" pilot that uses a 10 tooth Key. The K32 key has a 1/4" pilot and is the same as Rohm S9 and I believe the T5 key is the same as well.