Tamper-Proof Key Ring® technology provides you with the ultimate in strength and durability. These high security stainless steel rings cannot be opened without detection thus preventing asset removal or substitution. They may serve on their own as a high strength key ring or in conjunction with our electronic key safe as an added layer of protection for your most valuable assets. As a one time use security device our rings verify that items taken from a safe match the items returned. Tamper-Proof Key Rings® come in five different sizes of solid or flexible style and are used to secure assets from keys and utility knives to medical equipment and cash tills.