Although the '11 1/2 pattern has been around since the Case Brothers Era (1896 to 1915), the earliest documentation of the name "Cheetah" being used was in the early 1970's. The Cheetah pattern is one of the most storied of all Case knives. What makes this single-bladed knife so popular is its locking clip blade with the added safety of a swing guard. Throughout its existence, it has been manufactured with and without a swing guard, and with and without a locking mechanism. Some of the more recent knives are stamped with an "L" after the pattern number, which signifies that it has a clip blade that locks when opened. In 2002, after a 20 year hiatus, Case reintroduced this patten offering a redesigned and imporved knife.