Steel Climbing Frames, Steel Swing sets and Trampolines: Know about Galvanised Steel
Galvanised steel is an ideal choice for the manufacture of outdoor toys and play equipment. It is a man made, extremely robust and 
stable material which delivers significantly more strength per cubic cm than other materials including wood. So you need a far slimmer tube of steel compared to a pole of wood to deliver similar performance.
Unlike wood, galvanised steel does not change with atmospheric conditions- for example contact with water does not make it expand and contract. However, steel that is not galvanised is likely to rust, perforate and eventually fail when left outside year after year.
It is for this reason that TP chooses galvanised steel for Explorer and Challenger Climbing frames, the Giant Swing Frame Range and the Capital and Sovereign Trampolines. Only after the steel has been formed into a perfect tube is it then coated with zinc (galvanised). In fact it is triple coated with hot zinc, a conversion coating and finally a lacquer coating to give the toughest, most weather resistant protection possible