Intellikey System 4000 101257 Lock Programming Unit with EPU-L Clip. LPU with Emergency Power Unit-Lock interfaces between PC and locks and cylinders for both programming and auditing of locks and cylinders (Software and PC separate). Locks can be audited with LPU or audit key or by reading end-user keys with a KPU. USB to serial adapter included with KPU and LPU products below.