STANLEY tru zeroTrue Zero End Hook The end hook of the tapes also can move independently by up to the thickness of the hook. This means when measuring up to an object the hook moves in to compensate for the thickness of the hook allowing it to remain accurate. tylon coatingTylon Coating The Tylon coated blades are up to 1.5 times more resistant to abrasion than normal standard lacquered blades, giving improved longer tool life. 3 rivet end hook3 Rivet Hook By using 3 rivets rather than 2 this makes the end hook 40% stronger and so makes the overall tape more durable. class 2 accuracyClass II Accuracy The STANLEY Tylon tapes comply with European class II standards. This means the maximum permissible tolerance over 3 metres is less than a millimetre.