CLO4K CPU XL is an elite extra which contains 50 cloaks that make the player invisible until you launch an attack yourself, get EMP'd, or go into Pirate de-cloak mist. Compared to CLO4K CPU and CLO4K-MOD, it is the best out of the two due to having 50 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.
Cloak your ship 50 times and stay invisible until you launch an attack yourself.
WARNING: Enemies can still see cloaked ships on the mini map.
Only one of these items is allowed per configuration.