I've left mine in the trunk for almost two years wherever I went and NEVER had a problem with it. The saftey valve never popped open on me.
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-00 Civic EX Coupe BUILT D16Y8, Precision SC50, 12.80@105.8 14psi
-00 Chevrolet S10 LS 4.3L V6 Gas Guzzler
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