5/16-18 Roll-In T-Nut with Ball Spring 24 PACK Our Roll-in T-nuts with ball spring provide a fastening option that can be installed from the profile end or side, Perfect for applications where the ends are inaccessible. The ball spring holds the T-nut in the T-slot, even when the profile is in a vertical position, simplifying the assembly process. Compatible with 15 Series & 40 Series aluminum t-slot profiles with 8mm slot. Bright Zinc finish, 5/16-18 thread. Measures 13.5 mm x 7.2 mm x 22 mm long with a 5/16-18 thread and a ball spring Pack of 24 Individual T-Nuts