- Viega MegaPress is a carbon steel, cold press system designed for use in compressed air, fuel gas, and heating oil applications. Viega MegaPress fittings are designed for use in piping systems utilizing ASTM A53, A106, A135 and A795 SCH 5 to SCH 40/STD carbon steel pipe. Viega MegaPress fittings for fuel gas or fuel oil systems shall be used with ASTM A53 SCH 40/STD carbon steel pipe. MegaPress is CSA LC4 approved for fuel oil and fuel gas installations.