3.35 x 3.5 mm Self-Piercing Rivets (25 per pack)

3.35 x 3.5 mm Self-Piercing Rivets (Pack of 25)  They are specially-coated steel rivets that pierce the outer body panel and mushroom into the inner body panel without piercing it. A special coating, usually tin/zinc, prevents galvanic corrosion. A special tool is used to press the rivet into place and it must have access to both sides of the panel.