Redcat Racing 102049 Aluminum Nylon M4 Locknut, Purple (4pcs) ~ Works with these models ONLY: CALDERA 10E,CALDERA SC 10E,CALDERA XB 10E,LIGHTNING EP DRIFT,LIGHTNING EPX PRO,LIGHTNING STK,LIGHTNING STR,PAGANI,PAGANI/PAGANI PRO,S-TRYK-R,S-TRYK-R/S-TRYK-R PRO,SANDSTORM,SANDSTORM TK,SHOCKWAVE,THUNDER DRIFT,THUNDER EPX DRIFT,TORNADO BB,TORNADO EPX/EPX PRO,TORNADO S30,TREMOR SG,TREMOR ST,TWISTER-XB,TWISTER-XTG,VOLCANO EPX/EPX PRO,VOLCANO MX,VOLCANO S30,VOLCANO STX,VOLCANO SV,VOLCANO T2,VORTEX EPX/EPX PRO,VORTEX SS