Roof Vent Lid, Smoke, With Slide Bar, Bulk Package (90112-C1) by Heng's®. Replacement For Hengs/ Elixir Universal And Ventline Vents. Heng’s Industries USA, LLC is a premier manufacturer supplier of quality recreational vehicle and marine products. We provide a diverse series of quality products ranging from vents to sealants to affordable furniture supplying distributors th...