https://dragracesolutions.com/self-ejecting-quarter-turn-fasteners-5-16-hex-600-50pk/
Self Ejecting Quarter Turn Fasteners - 5/16" Hex .600 50pk
Hex Head Self Ejecting Quarter Turn DZUS Fasteners. Silver Cadmium Plated Steel - #5, 5/16" x .600 Long - 50pk / Made in U.S.A.
quarter turn fastenersself ejectinghex