Leatherman Folding Knives

The first Leatherman folding knives were introduced in late 2005. Since then, 55 models have been launched, and a whopping 49 of them quickly retired. It leaves just six current models. There have been nine series of knives (seven completely retired), with models in a wide range of body types (and often, confusing naming systems).

Leatherman currently lists two series of folding knives. The Skeletool KB and KBX were introduced in 2017. Their body and blade are similar to the knife portion of the popular Skeletool. The Free K2, K4, T2 and T4 were introduced in 2019. They are similar to one arm of a Free P2.
The Crater series of ten Leatherman knives was introduced in 2008. All Craters have 420HC stainless steel blades, carabiner, liner lock (push sideways to release), glass-filled nylon bodies, removeable pocket clip, and two-digit size numbers. X=serrated blade, L=blade launcher, T=screwdrivers and B=bit driver. All four bit driver models were retired in 2011, and the rest ended in 2019.
The Expanse series of ten Leatherman knives was introduced in 2008, and retired in 2011. All have a carabiner, liner lock and blade launcher, with 154CM stainless steel blades, combination metal and nylon bodies, and two-digit size numbers. X=serrated blade, L=blade launcher, T=screwdrivers and B=bit driver.
The "C" series of eight Leatherman knives was introduced in late 2006, and retired in 2008. All have a blade launcher, with 420HC stainless steel blades, a liner lock and 3-digit numbering. Even numbers are plain blades, and odd numbers are partly serrated. Numbers 302 and up have a carabiner. Numbers 304 and up have Phillips and slotted screwdrivers. Four have a contoured, glass-filled nylon body, and four have a slotted aluminum body.
The "E" series of eight Leatherman knives was introduced in late 2005, and retired in 2008. All have a carabiner, liner lock and blade launcher, and 3-digit numbering. Even numbers are plain blades, and odd numbers are partly serrated. Numbers 300 to 303 have a glass-filled nylon body and 420HC blade, while 304 and up are combination aluminum and glass-filled nylon with a 154CM blade.
The "H" series of four Leatherman knives was introduced in late 2006, and retired in 2008. All are lock-backs with 420HC stainless steel blades. Even numbers are plain blades, and odd numbers are partly serrated. H502/503 add a bottle/can opener and bit driver, with two bits stored in the body.
The "K" series of four Leatherman knives was introduced in late 2005, and retired in 2008. All are lock-backs with 154CM stainless steel blades. Even numbers are plain blades, and odd numbers are partly serrated. K502/503 add a carabiner, bottle/can opener and bit driver, with two bits stored in the body.
Five innovative lock-back hunting knives were introduced in 2007, and retired in 2009. They are larger than the other models, with names inspired by the geography of Oregon and Idaho.