Slant/fin multi/pak 80 – 4′ hydronic baseboard radiation for hot water this baseboard heater is made with rust resistant galvanized steel. Heavy duty 18-gauge front cover resists damage. H-3 element in 80d enclosure. 3/4 copper tubing with 3-5/32×2-1/2x.011 aluminum fins. Puts out 730 btu/linear ft. Using 180f water at 1 gpm. Reference specifications for additional ratings. Durable and economic design is ideal for light commercial buildings, apartments and residential applications. Optional accessories include: hinged right-hand & left-hand end caps and 90 inside corners and are sold separately. Easy installation.