Inline screw on adapter turns any paintball tank into an on/off. Fits standard valve threads on CO2 and HPA tanks. Quick turn of the knurled twist ring disengages the pin depressor stopping the flow of gas. This on/off eliminates the need to remove your tank. Compact unit adds less than 1.3"! Black anodized aluminum construction. 2 Inch long overall. Weight:1.6 oz.