The CL04K CPU is an elite extra which contains 10 cloaks that make the player invisible until you launch an attack yourself, get EMP'd, or go into Pirate de-cloak (blue) mist. It's better than the CL04K MOD due to having 10 cloaks. Be aware that you're still visible in the minimap. The only way to become completely invisible is to own a Spearhead and activate the "Ultimate Cloaking" ability.