Safer & more efficient use – MAXI – DRIVE Plus features a locking groove to prevent Spanner slippage. MAXI – DRIVE is ideal in use on damaged, frozen or rusted fasteners. These drive designs make Stanley Sockets & Spanners safer and more efficient to use than conventional tools. KIT INCLUDES9 × 1/4” Drive Metric Sockets – 4, 5, 6, 7, 8, 9, 10, 11, 12mm.9 × 1/4” Drive A/F Sockets – 3/16, 7/32, 1/4, 9/32, 5/16, 11/32, 3/8, 7/16, 1/2”.9 × 3/8” Metric Sockets – 8,1 0, 11, 12, 13, 14, 16, 17, 19mm.7 × 3/8” Drive A/F Sockets – 3/8, 7/16, 1/2, 9/16, 5/8, 11/16, 3/4”.2 x A/F Spark Plug Sockets – 5/8, 13/16”.1 × 1/4” Socket Accessory – Spinner Handle.3 × 3/8” Socket Accessories – Ratchet, Extension 75mm, 1/4” Male – 3/8” Female Adaptor. - Stanley Sockets & Ring Spanners (including Ring End of Combination Spanners) feature the MAXI – DRIVE fastening system. - Stanley Open End Spanners (and the Open End of Combination Spanners) feature MAXI – DRIVE Plus. - Fastening is made easier and tighter – Unique drive designs allow greater contact with the flats of fasteners, providing greater torque to make tightening easier. - Fasteners last longer – Conventional Sockets and Spanners damage fasteners by concentrating forces on the corners. - Stanley drive designs spread force over a larger contact area, reducing rounding off and extending fastener life.