~ The top and bottom plates are made of durable shock-resistant tool steel through hardened for long-wear. 7 Piece 1/4-5/8" Disc Cutter Set 7 Piece 1/4-5/8" Disc Cutter Set ~ Punches are made of case-hardened tool steel.
. Though they are designed to attach metal to metal they're also used to attach metal to wood fiberglass and plastic.A pre-drilled hole is required for installation. Sheet metal screws are fully threaded with a sharp point.