The KeySmart’s unique “S” shaped design allows you to hold between 2- 100 keys (with expansion packs, sold separately). Its compact size is smaller than a pack of gum (3 5/8″ overall). It is also universal, will fit almost any key found at your local hardware store! Includes loop piece to attach car keys. Made in the USA from aircraft aluminum, stainless steel hardware, and a laser engraved logo. Base model holds up to 4 keys, expansion packs for 5+ keys are available (sold separately).