eXtremeRate LB RB LT RT Bumpers Triggers D-Pad ABXY Start Back Sync Buttons, White Full Set Buttons Repair Kits with Tools for Xbox One S & Xbox One X Controller (Model 1708) –
Replacement Part LB RB Bumper Button and Front Damper for Xbox One Elite Controller - Newegg.com
Wireless Xbox One Controller Bumper Assembly Replacement - iFixit Repair Guide
Amazon.com: New Replacement Bumpers Triggers LB RB Buttons&Middle Piece for Xbox One Slim Xbox One S Controller. : Video Games
Left Bumper busted loose somehow. Any fixes? : r/xboxone
2017 How to replace Xbox One controller Bumper buttons - YouTube