Holsters suitable for securely retaining an item, such as a handgun, to an individual that enables removal of the item with a single hand when the individual is in a sitting position. Such a holster includes at least first and second holster subcomponents that have at least first and second partial cavities, respectively. The first and second holster subcomponents are assemblable to align the first and second partial cavities to define a pocket that is configured so that the first and second holster subcomponents are interlocked together to define the holster when an item is placed in the pocket and the first and second holster subcomponents are simultaneously released from each other in response to the item being removed from the pocket.