Improved lock core with sidebars

A pin tumbler lock, including a lock core adapted to rotate inside a shell, the lock core including a body, one or more side bars, a keyway, and tumbler pins located in bores in the body, the or each side bar being adapted in a projecting position to project from the outside of the lock core into a corresponding recess in the lock shell, and in a released position to be received into the core when a correctly coded key is inserted into the keyway and engages the tumbler pins, so that operatively the lock core can be rotated relative to the shell when the correctly coded key is inserted, wherein the body includes a retention component, separately formed and including engagement features to retain the or each side bar when it is/they are in the projecting position and wherein the retention component further includes one or more of said bores and corresponding additional tumbler pins.