Which LockNFlate® Air Chuck do I need? Open Flow or Closed Flow? 

Like no other air chuck on the market, the LockNFlate's six steel jaws lock onto any Schrader valve to create a secure, hands-free connection. The heavy-duty construction is built to last and stand up to everyday use in even the busiest tire shops, service bays, and garages.
Depress the thumb lever and push onto the tire valve until 1-2 threads remain exposed at the bottom. Release the lever to lock the air chuck in place.
• SIX STEEL JAWS lock onto any Schrader tire valve to create a secure, hands-free connection
• 1/4” NPT HOSE CONNECTION: compatible with most air hoses
• RATED TO 150 PSI: Suitable for all air systems including garage, industrial, auto, and manual tire inflators, portable pressure gauges, constant pressure systems, and more!
AVAILABLE IN 2 STYLES: Open Flow or Closed Flow
• OPEN FLOW: Air passes through freely on or off the valve stem. For use with inflator gauges and automatic systems.
• CLOSED FLOW: Must engage the tire valve for air to flow. For use directly from a compressor or air hose.
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