Industrial TireChina 8" O. D. X 2 13/16" ID, 6 5/8 Reg, 150 Ppf Spiral Drill Collar: 8 1/4" Outside Diameter X 2 13/16" Inside Diameter, with Slip Recesselevator Recessno Hard Band, Find details about China Spiral Drill Collar, Mud Motor from 8" O. D. X 2 13/16" ID, 6 5/8 Reg, 150 Ppf Spiral Drill Collar: 8 1/4" Outside Diameter X 2 13/16" Inside Diameter, with Slip Recesselevator Recessno Hard Band