Astro Pneumatic Tire Inflator Dial Gauge 3081 The Astro Pneumatic Tire Inflator Dial Gauge 3081 is an aluminum die-casting unit covered with rubber sleeve for extra comfort and durability. Clear and easy to read, the Astro Pneumatic Tire Inflator Dial Gauge 3081 has a 3-in-1 function: inflate, deflate and measure tire pressure. Two position inflate/deflate lever grants increased safety and reduced tire-related incidents. Works with CO2 (carbon dioxide). Unit includes a 21” hose. 3-18” (80mm) pressure gauge (0-12 Bar/174Psi). Diameter of the dial: 3-1/8” (80mm).