Check the listing for details. Align Trex 450L PRO DFC Slant Thread Main Drive Gear/121T (one) H45156QA. Condition: New. Listed at 7.45 USD. Align Trex 450L PRO DFC Slant Thread Main Drive Gear/121T (one) H45156QA Part Pull From A Trex 450L DOMINATOR kit Contains ONE PIECE Must with:H45157 Motor Pinion Helical Gear 12T This updated high strength 121 tooth main gear features Mod 0.6 gears perfect for 450 helicopters. The increased gear pitch can withstand higher powers while at the same time minimizing operational noise. This gear is a great upgrade to withstand modern high power systems. Features: Utilizes high strength polymer plastic with excellent rigidity and flexibility characteristics Mod 0.6 gears to withstand modern high powered systems Patented unique built in fan design to create induced air flow, effectively cooling electronics and motor Specifications:Gear ratio: 1:10.08Weight: 35.3g Part Pull From A Trex 450L DOMINATOR kit Contains ONE PIECE Must with:H45157 Motor Pinion Helical Gear 12T This updated high strength 121 tooth main gear features Mod 0.6 gears perfect for 450 helicopters. The increased gear pitch can withstand higher powers while at the same time minimizing operational noise. This gear is a great upgrade to withstand modern high power systems. Features: Utilizes high strength polymer plastic with excellent rigidity and flexibility characteristics Mod 0.6 gears to withstand modern high powered systems Patented unique built in fan design to create induced air flow, effectively cooling electronics and motor Specifications: Gear ratio: 1:10.08 Weight: 35.3g