10L0L 3/8 Inch Open-Ring Cap Gripper Grip Prong Stainless Steel Snaps No-Sew Button Fasteners Studs, Fastener Pliers (snaps Pliers and 100-piece snaps) 50 pieces open-ring caps, 25 pieces of each socket/female andd stud/male for make 25 complete sets of snaps Out diameter of socket and stud are 3/8 inch. Approx are 3mm long,sufficient for most sewing fabrics but not intended for use with thicker or dense fabrics. Snaps are made of stainless steel. Dualable and long lasting.