Neck Size 1 1/4" O.D. About JB Tools. Milton 500-7 Single Head Chuck Washer / only 1. Grey Pneumatic 81024R 3/8" Drive x 3/4" Standard Duo-Socket - 6 Point. Milton 684-4 1/4" NPT Tank Valve. If you receive a defective product, so long as the Limitations found within JB Tools?.