Medical Gas Markers are adhesive backed labels you peel and stick, designed to wrap completely around pipes ranging from 3/8″ to 3/4″ in diameter. Rolls contain 100 markers at 3″ x 3″ each. Use on pipes ranging from 3/8″ thru 3/4″ in diameter. Spec Compliance: NFPA 99C & CGA C-9. Medical Gas Pipe Labels, Nitrogen Labels, Seton Pipe Marker, Seton Pipe Marker Nitrogen.