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The Umnumzaan is a folding pocket knife manufactured by Chris Reeve Knives of Boise, Idaho, and designed by Chris Reeve. The name "Umnumzaan" is derived from the Zulu language, meaning "Head of the family," or "Boss" (colloq.), a tribute to Mr. Reeve's South Africa origins.〔The Umnumzaan was designed to meet the needs of operators seeking a heavy-duty folder capable of handling heavy use and even abuse. Building upon the Sebenza’s success, the Umnumzaan features: a stronger pivot joint, a thicker blade, a different blade grind with a reinforced tip, improved ergonomics, thicker titanium handles, a thicker titanium lock bar, a stronger ceramic ball detent system, a larger titanium spacer (sometimes called a “stand off”), a phosphor-bronze washer system designed to act as a ‘dry-sump’ to retain lubrication and keep dirt out, an oversized ambidextrous-thumb studs & extended lock bar to aid operation when wearing gloves, a lanyard pivot joint that uses pivoting lanyard tie bars, and a deeply textured grip. ==Design== The Umnumzaan implements a version of the Chris Reeve Integral Lock.〔(Integral Lock Design Principles on the Sebenza )〕 The original Integral Lock (sometimes referred to as the “frame lock” or“titanium frame lock”) developed by Reeve in 1987, was first implemented in the Sebenza folding pocket knife. This lock employs a titanium lock bar, milled out of the knife's handle material. At lock up, the titanium lock bar comes in direct contact with the back of the blade, thus locking the blade in the open position. The Umnumzaan Integral Lock utilizes a ceramic ball that serves two functionsthe ball acts as the interface between the blade locking surface and the integral locking arm as the knife assumes the open position.〔Shackleford, Steve, Blade Magazine, The Blade Magazine 2008 Knives of the Year, October 2008, p. 12〕 The ball also mates with a detent in the blade in the closed position to secure the blade from opening accidentally. The Umnumzaan blade pivot is implemented with a pivot screw and pin, and is supported by perforated phosphor bronze thrust washers. The functions of the perforations are to reduce friction due to a reduction in surface area relative to that of a solid washer, and to increase the duration of use between cleanings by housing lubricant in the perforations.〔 Over the life of the Umnumzaan, the pivot and washers have been incrementally modified. The thumb lug on the Umnumzaan is used for opening the knife blade, as well as serving as the stop pin that contacts the titanium handle slabs upon lockup. Around each lug is a polyurethane o-ring that acts as a shock absorber to cushion the shock of opening, and reduce the audible noise of opening. The use of the shock absorber concept was pioneered by knife designers Grant and Gavin Hawk, and is being implemented in the Umnumzaan with their consent.〔(Official Umnamzaan Datasheet )〕 The knife also features a glass-breaker, but unlike many other glass-breakers on folding knives, the tip is part of the blade itself which protrudes from the pivot side when the knife is closed. The Umnumzaan also was the first Chris Reeve folding knife to incorporate a lanyard pivot joint, which dramatically reduces the friction wear that over time destroys paracord lanyards. It also allows easy swapping of lanyards without a need to cut and retie if the owner has multiple lanyard pivots (referred to as a “cord tie bar” by Chris Reeve Knives). The lanyard pivot joint has since been incorporated on the Sebenza Classic 2000, Sebenza 21, and Sebenza 25. The specifications of the Umnumzaan are as follows:〔
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