Silverline Auto Blade Lock Tape Display Box - 30pce 3m / 10ft x 16mm. Features a scratch-resistant, nylon-coated blade with clear metric and imperial graduations. Includes highlighted joist marks every 16". The tape has an automatic lock when extended and a retraction button. It also has a triple-riveted end hook and a belt clip for convenience. Measures internal and external lengths. Conforms to EEC Class II.