Heat Seaming. Seam irons from Roberts and Crain Tools, 110v Crain iron for site work. Includes related products, Seam rollers, Heat seaming tape, Napping Shears to name just a few. A must have Crain Heat Seam Iron Box, pack your iron away no waiting for it to cool down. Loads of room under the iron tray for the lead, shears and seam tape.