Additional Details ------------------------------ Product description: Type L copper tubing has thicker or denser walls to handle greater pressures than Type M tubing. Type L hard tubes are found indoors to supply potable water, carry hot water, and supply water to sprinkler systems. Type L flexible roll tubing is easier to use underground and outdoors, doesn?t need fittings, and eliminates concerns about water wearing tubing down due to high pressure. Medium-pressure applications include plumbing, potable water service and distribution, fire protection, fuel/fuel oil, natural gas, LP gas, HVAC, compressed air, and vacuum. ASTM specifications are permanently marked or incised in blue to distinguish between other copper tube types.