... ,23,243/8" x 3/8"10.6mm x 10.6mm19,20,21,221/2" x 1/2"12.7mm x 12.7mm16,17 ... ,15,16,17,18,191" x 2"25.4mm x 50.8mm14,15,162" x 2"50.8mm x 50.8mm12,13,14,15 ... (mm)1/2" x 1/2"12.7mm x 12.7mm16,17,18,19,20,213/4" x 3/4"19mm x 19mm16,17,18 ... ,19,20,211" x 1"25 ... .4mm x 25.4mm15,16,17,18 ...