Slant Thread Main Drive Gear/121T (Black) X3: H45156QAT

\u25CFUse for T-REX 450 Series.\u25CFMust with::H45157 Motor Pinion Helical Gear 12T.\u25CFNew style high strength 121 tooth Mod 0.6 helical main hear for 450 size helis. The increase gear pitch can withstand higher power, at the same time minimize operational noise. A great upgrade to withstand the modern high power system.\u25CFUtilizes high strength polymer plastic with excellent rigidity and flexibility characteristics.\u25CFPatented unique built in fan design to create induced air flow, effectively cooling electronics and motor.\u25CFGear ratio 1:10.08.