UL stands for Ultra Light and is a range of Stratis surfaces that is light, strong and performs very well in race conditions. The product is constructed of a very light BOPET film laminated to an extremely light woven Taffeta, as far as we know the lightest woven membrane component to date and exclusively produced for Doyle.

The weight of the UL range is one of the main success stories in the Stratis membrane grand Prix and race components


The Ultra-Light Taffeta that is laminated to the BOPET film gives the product sufficient resistance against abrasiveness from general racing conditions.


All UL range membranes that are made in our Stratis facility have used the Stratis Adhesive System. The principle behind this system functions in a twin pronged approach. One adhesive system is first applied to the surface of the UL. This adhesive is ‘inert’ and shelf stable at room temperature. During the membrane production the fibres are coated in-line with a low viscosity ‘reactive’ adhesive system. The reactive system chemically binds to the adhesive system on the UL surfaces. After lamination a B-stage cure continues at room temperature for several days.


As with all products, the UL range is tested in house in the laboratory humidity chamber, here we test the resistance against mould growth inside and outside of the product.


Every order of the UL range is peel tested for resistance against the bond between the BOPET film and the Taffeta substrate. Peel strength tests are provided by the manufacturing facility as well as in-house at our New Zealand facility.

(Image: YD37 Anarchy with different variations of UL for headsail and mainsail)


The UL range comes in 2 variations with each a range of colours.

The UL 0.25 is a 0.25mil = 0.00025 Inch or 0.006mm thin BOPET film laminated to the Ultra Light Taffeta with a very light amount of laminating adhesive.

The UL 0.5 is a 0.5mil = 0.0005 Inch or 0.0127mm BOPET film to which the Ultra Light Taffeta is laminated to.

UL 0.25 has a natural polyester Ultra Light weave with no added white pigments, this is the lightest product in the range and is used mainly in Code Zero’s and Gennakers.

UL 0.5 Natural and White are only used for the Doyle Stratis Sail Art, it gives the same performance as any other 0.5 UL product.

UL 0.25 Titanium was especially developed for the Stratis Titanium ICE range but was so popular that it is now widely used for all light weight race sails.

UL 0.5 Titanium was also part of the initial Stratis Titanium ICE range but is a product that has seen many applications from main sails to Superyacht Gennakers.

UL 0.25 Black is used by a high variety of Grand Prix race teams as a high performance product that has seen many positive race results.

UL 0.5 Black used by many Grand Prix teams as a very light membrane component to create the ultimate race weapon.


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