Screwdriver inserts with titanium coating up to 600 % harder than standard CR-V steel. Square socket drive to DIN 3120. Safely located against loss in a practical rail. The rail has 2 drilled holes, so can also be wall mounted. Contents: Dimensions: L= 59 mm/depth= 21.50mm. approx. 1/2": PZ1 / PZ2 / PZ3 / PZ4