Black oxide carbon steel Improved internal lock mechanism Spun rivet construction Approved by the National Institute of Justice The classic design is new and improved. The Model 701C features an improved internal lock mechanism for increased tamper resistance, smoother ratcheting action and greater durability. The 701C incorporates spun rivet construction, push pin double lock capability and black oxide finish. Two keys supplied. The Model 701C is made to meet National Institute of Justice Standard 0307.01. Made in USA.