... size:1.5", 2", 2.5", 3, 3.5", 4", and 4.5", 6", 8", 10",Pressure range:-30" Hg-0 ... steel or chrome plated steelWindow (lens):Glass, acrylic, and polycarbonate lens availableDial plate:Single and dual scale (psi, kpa, mpa, bar, kg ... available3) Back flange available4) U-clamp available5) Other connection sizes available upon request.