PT 30017 Ring Gear fits RIDGID &reg; 300 Pipe Threading Machine 30017 30017 Ring Gear Fits RIDGID  300 Pipe Threader (1) PT 30017 Ring Gear Fits RIDGID  300 Pipe Threader. Also fits PT  300 Pipe Threading Machine. Replaces Ridgid 30017 Ring Gear. Quality alternative to Ridgid parts.