Scratch-resistant, nylon-coated blade. Clear metric and imperial graduations with highlighted joist marks every 16″. Automatic lock when extended, retraction button, triple-riveted end hook and belt clip. Measures internal and external lengths. Scratch-resistant, nylon-coated blade. Clear metric and imperial graduations with highlighted joist marks every 16″. Automatic lock when extended, retraction button, triple-riveted end hook and belt clip. Measures internal and external lengths.