Made with a hard wearing 600D polyester outer laminated to an open cell foam with a brushed tricot lining that allows any spars contained to breathe - which prevents corrosion.  The bag can take a spar up to 3650mm, but will easily fold down to take smaller spars if required. 
This bag length is suitable for a Laser top mast, Aero top mast, Aero 9 Lower Mast, Lightening upper and Lightening Lower mast.