Overview Reviews Product Description The 2000L and 2500L are automatic pressure and vacuum relief caps for farm and industrial fuel storage tanks.The normally closed relief valve prevents fuel evaporation and dust contamination.It vents at 2 psi pressure or 0.7" Hg vacuum.The body has an NPS male threaded body with a lockable cap (padlock not included). Greenline Industrial Fitting Catalog New Greenline Industrial Fitting Catalog Product Videos Custom Field Product Reviews Write a Review Write a Review × Greenline 2-1/2" NPT Locking Vent Cap 2500L Rating * Select Rating 1 star (worst) 2 stars 3 stars (average) 4 stars 5 stars (best) Name Review Subject * Comments *