Spec Manufactured from drop forged steel Spring loaded jaws Teeth on upper and lower jaw serrated in opposite directions for a secure grip Easy adjusted jaws with knurled adjustment nut Designed for heavy duty use Ideal for plumbers, engineers and builders etc Max Jaw Opening Size Approx 8' approximately 3.5cm (1 1/2 ') 10' 50mm maximum opening 14' 2 1/2' maximum opening 18' 3' maximum opening 24'3 1/2' (90mm) maximum opening 36' 4 1/2' maximum opening Please note the 8' is blue in colour