The Forney 75554 0-160 PSI 2-1/4-inch air line pressure gauge with bottom mount 1/4-inch NPT is a bottom mount. Not suitable for liquids or other gases. Forney Industries is one of Americas longest operating family-owned metal working product companies. Founded in 1932, Forney offers more than 5,000 products for the hardware, automotive, farm and ranch and do-it-yourself markets. If you've got metal working questions, we've got answers. Were committed to your success regardless of location size or needs. 0-160 PSI 2-1/4-inch (57.15mm) air line pressure gauge with bottom mount 1/4-inch (6.35mm) NPT. Proof of purchase required. neglect, negligence or accident, or that has been used in any way contrary to the purpose intended.