Grex Genesis Ergonomic Airbrushes are set apart by the exclusive Ergonomic Airbrush Grip Set, a two-piece system that easily slips over the main body and trigger. Made of a silicon-based polymer, it's soft enough to relieve pressure points, yet firm enough to provide structure and improve handling. - Grex Genesis Ergonomic Airbrush- 0.3 mm Tip, Bottom FeedGrex Genesis Ergonomic Airbrushes, 0.3MM DB ACT BTM FED - The Genesis XBi3 features a 0.3 mm nozzle and three interchangeable reservoirs; one 7 ml (1/4 oz) and two 30 ml (1 oz). The plug-in siphon bottles and cups allow for quick and easy color changes while you work. The XBi3's design allows for precise control for fine detailing and is suitable for small- to medium-size work.