Tusa Alternate Air SourceThe SS0002 Duo Air II is an alternate air source that also provides you with an easy-to-operate power inflator. The SS0002 features a power inflate button, manual inflate/deflate button, large diameter purge button, and a low profile mouthpiece.FEATURES:Downstream alternate air sourceAir balanced power inflatorLarge diameter purge buttonPower inflate buttonManual inflate/deflate buttonLow profile mouthpiece