Model Number: HF drill rod-#4618 Brand Name: HF Key Specifications/Special Features: Features:1. Carefully selected seamless steel pipe and high quality alloy steel for joint tools2. Precisely friction welded to ensure straightness and concentrically3. Multiple precisely heat-treated tools joint4. Internally and externally upset drill rods are available Diameter (mm)Diameter (inch) Connection thread Length 76mm 3" API 2 3/8" reg 1-6m 89mm 3 1/2" API 2 3/8" reg 1-6m 102mm 4" API 3 1/2" reg 1-6m 114mm 4 1/2" API 3 1/2" reg 1-6m 127mm 5" API 3 1/2" reg 1-10m 140mm 5 1/2" API 3 1/2" reg 1-10m 152mm 6" API 4 1/2" reg 1-10m