Straight Barbell Stainless Steel Sizes: 18 Gauge (1mm), 16 Gauge (1.3mm), 14 Gauge (1.6mm), 12 Gauge (2mm), 10 Gauge (2.5mm), 6 Gauge (4mm), 4 Gauge (5mm), 2 Gauge (6mm) Length: 1-1/2" (38.1mm), 1-1/4" (31.8mm), 1" (25.4mm), 3/4" (19mm), 5/8" (15.9mm), 1/2" (13mm), 7/16" (11.1mm), 3/8" (10mm), 5/16 (7.9mm)