80/20 Inc., 3320, 15 Series, Bolt Assembly: 5/16-18 x .687" Flanged Button Head Socket Cap Screw (FBHSCS) and Slide-In Economy T-Nut (25 Pack) Go to amazon.com Related posts Best t-nuts 5/16 Featurew Slide-In15 Series compatible Description5/16-18 X .687" Flanged Button Head Socket Cap Screw (FBHSCS) and Slide-In Economy T-Nut. You will receive 25 screws and 25 t-nuts with each order.