Heavy-Duty Aluminum Benches?provide affordable, low-maintenance seating for players and fans?• Seats and backs are comprised of 10" wide anodized aluminum planks?• Frames are constructed of 2-3/8" heavy-guage galvanized steel for maximum support and years of use?• Available in 8', 15', or 21' lengths?• All sizes and styles available in?portable, permanent, or surface mount installation?• Optional indoor conversion kit (includes non-marring floor protectors an attachment hardware) for portable models is available for an additional cost?