... K copper tube is thicker than type L and type M. The max wall thickness we can make ... than type L and M and are used for domestic water, service and distribution, fire protection, solar, fuel and oil, HVAC, ... air, oxygen, LPG gas, snow melting, steam and vacuum systems. -copper tubes of type K can be ... used sweat, flared and compression fittings. Available in hard and soft types.10.Picture of type ...