10 piece set with the complete Phillips set P1 - P4, and flat tip drivers 3.3mm - 12mm wide blades. S2 Steel, the strongest hardest drivers available. Knurled body for fingertip control. Satin Chrome plated, and marked for easy identification. Lifetime Warranty This Stubby Flat and Phillips set, is designed as a socket wrench attachment set for close quarter work. Each driver has a 1/4" Square drive and a Phillip or flat tip. All drivers are made with S2 steel and heat treated. Designed with the strength and durability to last!