Anti-Siphon Tube for Peterbilt diesel tanks. Length 6-3/4 Inches Designed to allow easy filling and restrict siphoning. Easy installation! Does not restrict fueling and there is no splash back. Less expensive than locking fuel caps. No Keys To Lose! Made in the USA Peterbilt locking cap is FTA-C-67-P, Not to be used with Anti-Siphon.