Caribu Sierra - 1680 Denier Waterproof Turnout Rainsheet Combo Horse Rug. The Sierra is our premium turnout rainsheet combo horse rug and is constructed from strong 1680 Denier - our flagship premium fabric. The Sierra combos feature our new Aeromesh linings - is a new generation open lining, very strong, but very soft on a horses coat. The Aeromesh is very hygienic and creates a breathing space between the rug and your horse's coat, this has multiple advantages - it greatly improves breath-ability, airflow and comfort for your horse and won't rot or attract mould as a cotton lining will. Aeromesh is used across the horse's body with Anti-Rub lining in the entire mane, shoulders and skirts. Incorporating European style 'Quick release' chest buckles with extra adjustment, very generous skirt lengths and reflective bindings & seams for added night safety. A great design with quality materials and superior construction. What sets our 1680 Deniers Turnout horse rugs apart from others? Our Sierra Rainsheets include reflective bindings & seams for added night safety as standard. Dual European style 'Quick release' chest buckles with extra adjustment options. Very Generous 'Full Wrap' tail flaps All Caribu Synthetic Rugs and Combos are rated to a waterproof rating of at least 3000MM - more than twice the minimum requirements. Our Synthetic Rugs also have have a breathability rating of at least 3000gr/m2/per24hrs. The waterproof rating relates to the fabric. No rug is ever 100% waterproof, as water will enter via seams & joins that can not be heat sealed (ie behind chest buckles, leg straps and tail flap joins). The continuous neckline also helps to reduce mane rubbing.