4-40 Future Thumb Nut with Set Screw - Blue (2pc) (JCO5240-1)

Blue aluminum 4-40 Future Thumb Nuts with Set Screws offer a quick, secure way to mount and swap battery packs in popular RC cars, replacing traditional screws and washers for faster installation and removal. This two-nut set presses into the battery brace and features a spiked perimeter for easy grip, along with a JC logo for authenticity.

Designed for 4-40 threads, the kit includes 5/8-inch long set screws to install into battery cups or buckets before seating the thumb nuts. Made from lightweight aluminum and finished in blue anodized or stealth black finishes, these thumb nuts suit a range of battery brace applications in models like RC10 and RC10T, delivering a durable, low-profile solution that speeds setup and maintenance.