More and more paintball players are depending on the protective capabilities of under-the-jersey chest protectors. The SystemX Chest Armor was designed specifically for paintballers who prefer additional protection from stinging welts. A thin, lightweight Biofoam chest plate with large ventilation louvers is mounted to a vented, stretch Lycra® fabric. It also includes a non-restrictive collar and form-fit design that doesn't restrict any range of motion. This is a very slick low-profile lightweight design that is almost invisible under your jersey.
The System X NME Chest Armor is older, so while it may be available used and in a few cases new, it is not commonly available anymore.