Team Redcat Upper Arm Hinge Pin 4x48mm (2 Piece) Redcat Racing Upper Arm Hinge Pin 4x48mm (2pcs) Genuine Redcat Racing Spare Parts Redcat Racing Part Number 505130 For troubleshooting and warranty information please contact a Redcat Racing Customer Service Specialist at 602-454-6445 or by emailing amazonsupport@redcatracing.com NOTE: Please read the User Manual before use.