This is very probably the toughest d lock money can buy principally designed for use on motorcycles the granit extreme is suitable for any high risk application a 16mm square section parabolic shackle is double bolted into the twin powercells of the armoured hardened steel body providing colossal pulling resistance the latest generation x plus key mechanism offers 1000000 key variations to shrug off any attempts at picking the granit extreme 59 is the absolute business please note this loc