Sea to Summit Comfort Deluxe S.I. Mat Double Byron Blue

The Comfort Deluxe mats are suitable for car camping or for extended basecamp-style trips – the envy of your friends is guaranteed. The Camper Van version was specially developed for the T5 and T6 California from Volkswagen: The cut-out at the corner allows it to be rolled out for a perfect fit. Of course, it also fits other vans.

Delta Core
The Delta Core system maximizes the comfort and thickness of the mattress while minimizing weight and bulk. The patent-pending coring process removes 40 % of the initial volume of the PU foam, giving us a minimal packed weight and size. Importantly, this coring technique has the additional benefit of keeping the top and bottom surface of the PU completely intact. This ensures consistent warmth along the full length of the mattress, avoiding the vertical holes or frame-like gaps that have traditionally allowed warmth to leach downwards. The full foam surface also provides significantly improved bonding of the foam to the shell fabrics of the mattress, thereby greatly reducing the chance of delamination. The shape and size of the Delta Cores are adjusted across the different thicknesses of our mattresses to ensure strength and durability, while still giving the user excellent support and self-inflating performance. The horizontal Delta Core technique is used in or Comfort Light SI, Comfort Plus SI, and Comfort Deluxe SI models.

PillowLock System
The Pillow Lock is designed to keep your pillow exactly where it belongs – on your sleeping mat. Sea to Summit’s unique PillowLock Velcro comes standard with all sleeping mats.

Multi Function S.I. Valve
When you pack your sleeping mat, the foam keeps trying to inflate. For this, Sea to Summit has specially designed the “one-way” inflation valve so that it is reversible and prevents the mat from sucking in air again. This makes it possible to roll out the mat as small as possible without having to fight against re-inflation. Compact and low profile, this valve allows faster inflation than traditional screw valves, offers easy pressure fine-tuning and super-fast deflation speed.

R-Value
The R-value (resistance value) is an indicator of how effectively the sleeping mat resists heat loss. It also determines how the mat protects against body heat escaping through cold floor temperatures (which can be much colder than air temperatures). This value can be tested internally, but at Sea to Summit all mats are independently tested in a laboratory to closely controlled standards. The new industry standard ASTM F3340-18 testing was introduced in 2019 and all Sea to Summit mats released since 2020 will be tested to this standard.