Our Model 506, or "Old Faithful" as we like to call her is our original rack.  She will hold 6 of any size tank available, with boot, comfortably.  Her rectangular 2 x 3 design makes her the most stable rack on the market today and her non marking feet assure you that she won't leave any paw prints on your deck.  The 506 is virtually unstoppable and is designed from the finest materials right here in Florida to offer you countless trips to your favorite dive spot or down the road in the bed of your truck.  Give the old girl a try, she won't let you down. Shown with BC Holder.