BS7553 Class G Recognised standard.Fits opening from 508x432mm wide.Floor to floor height 2.3-3m will fit most standard applications.Simple to install, complete with fitting instructions.Pivot arms smoothly control descent/ascent of ladder in and out of loft hatch.Metal safety catch prevents premature drop during sliding ladders operation.Wide comfortable, flat and anti slip treads for comfort extra stability and safety.Box section stiles give greater tortional rigidity.Maximum safe load 100kgs.Handrail for extra comfort safety and confidence by user