‘The IRWIN Pro Touch Combi Pack features Retractable and Fixed pro touch knifes and 10 Bi Metal blades. Both knives feature easy tool-free entry, convenient internal storage for 5 blades, magnetic blade retention and a ProTouch feel for a secure grip and greater comfort. The Bi Metal blades feature patented technology which fuses two premium steels together. This creates utility blades that are exceptionally durable, shatterproof and last 3 times longer.