The Ion is an electropneumatic paintball marker manufactured by Smart Parts. At the time of its release, the Ion was the first fully electropneumatic marker aimed at entry-level players, at a price point similar to Spyders and other mechanical blowbacks. The Ion has generally been credited with making high-rate-of-fire electropneumatic markers generally available, at a time when electropneumatic markers were considered out of reach of most casual or budget players. The original Ion was released in 2005, and soon soared in popularity, though it was often criticized for being difficult to disassemble and service. Smart Parts addressed these concerns in 2007 with the release of the Ion XE, which allows the bolt to be removed from the back of the marker. Features The Ion's receiver consists of a breech and firing chamber, both hard-anodized. Its grip frame and ASA are both made of die-cast aluminum and are powder-coated. The outer shell of the Ion is polymer. The Ion includes the Vision system, or eyes, an infrared emitter and receiver on either side of the chamber. This prevents the Ion from firing when a ball is not fully loaded in the chamber, reducing the number of "chopped" balls. The Ion is highly customizable: it is sheathed in a removable polymer shell, which comes in several different colors. This shell can also be replaced with aftermarket "body kits" to change the appearance of the Ion, similar to the kits available for the Tippmann A5 marker and others. These body kits also affect the performance of the gun and accessibility of the bolt. Body kits such as the lucky and deadlywinds are BOB (bolt out the back), and allow easy access and cleaning of the bolt. In addition to these body kits, several aftermarket replacement parts such as triggers and feednecks are available. The Ion board is manufactured in two forms: one intended for distribution in the United States, and another for distribution in the United Kingdom. The UK version of the board does not have burst or fully automatic firing modes and is identified by the green power LED. The US version of the board includes all firing modes and has a red power LED. This board can also be replaced with a number of aftermarket boards (such as Blackheart or Virtue boards) which offer greater control over the timing of the firing action, different firing modes, and a higher maximum rate