Grex Genesis Essential Set Double Action Airbrushes are reliable, high-performance tools for budget-conscious artists who still want the great features and benefits of the Grex airbrush system. Precision machining and carefully selected materials ensure consistent performance. They feature stainless steel nozzles and needles, durable, heavy nickel chrome-plated housing, and replaceable, solvent-proof Teflon seals. - Grex Genesis Essential Set Double Action Airbrush - XBi5-ES, Siphon Feed, 0.5 mmXBI5ES .5MM D ACT BT - The Genesis XBi5-ES includes a 0.5 mm needle and nozzle and an interchangeable 30 ml (1 oz) bottom-mount reservoir to offer a better line of sight. The plug-in siphon bottles and cups allow for quick and easy color changes while working and the preset adjustment knob offers precise paint volume control. The XBi5-ES features a new nozzle design to improve air flow and durability and is ideal for medium- to large-size work.