Product Information Material: Steel Select a Product Part NumberThread SizeBody SizeLength 3KMMS1615M16 x 1.53/8"2.68" (68.0mm) 3KMMS1815M18 x 1.53/8"2.70" (68.5mm) 4KMMS1815M18 x 1.51/2"3.06" (77.8mm) 4KMMS2015M20 x 1.51/2"3.11" (79.0mm) 4KMMS2415M24 x 1.51/2"3.21" (81.5mm)