6' Sfty Tube W/DP Valve HIGH VISIBILITY DESIGN: SMB is a 6ft marker that is a high visibility design, padded inflator cover and bright 'Diver Below' markings EASY USE: Unique design allows diver to inflate tube by free flowing air from the regulator. SMB can be filled by pushing in the inflator valve tube in with the inflator hose or through oral inflation. The air enters the tube through this valve at bottom. RUPTURE RESISTANT: Made from a 420 denier Nylon Fabric with a TPU coating for added strength in all water conditions to ascend without rupturing. Includes safety whistle Unique opening at bottem allows diver to inflate using free flow from regulator