Specifications include, but are not limited to: REGULATORSRegulator size shall be standard such as 350, 590 (zero gas), 660 (NO in N2) etc. unless otherwise indicated when call is made for delivery. CYLINDERSCarbon monoxide in air, methane in air, and nitric oxide in nitrogen shall be in lined aluminum cylinders. The lining shall be spectroseal or approved equal. The calibration gases shall maintain a stability of plus or minus 5% over a two year period. The manufacturer shall supply on demand data showing that stability is maintained by at least six months or experimental testing. RENTED CYLINDER INVENTORY An estimated inventory of rented cylinders is included in this bid document. The inventory is approximate and is informational only.