Our new Vortex Cuddy Cabin boat covers are made for boats with cuddy cabins, taller rails on front, taller console, etc. . These are the best boat covers available. They are suitable for storage/mooring as well as trailering. The cover is made from marine grade polyester. The cover is made from 7.8 oz/600d/600 denier solution dyed polyester. 600d is an indirect measurement of density and weight. The higher the number, the heavier, thicker, and heavier duty. This is the thickest cover you will find. You will see a lot of 300d, even 150d covers, which are proportionally half as thick and 1/4 as thick as our covers. The fabric is then coated twice with polyurethane on the bottom or downside, UV protected, and sealed. What this all adds up to is the best cover available. It is nearly twice as thick as what you see readily available commercially. It is designed to keep water out, as it is WATERPROOF. Yet, water vapor can permeate it, so it will keep moisture out, but will not keep moisture in! Our covers come with tie down/hold down straps, as well as a storage bag. For certain applications, such as higher speed trailering, you may need to add extra straps. The material is heavy duty enough to support any reasonalbly paced trailering. These also have elastic around the bottom, for super snug fit. It is not a disposable type cover. It is made for years and years of use. It has a 5 year warranty.