Designer's Notes Natural Highs is a moniker for the mountain lifestyle, where nature is our dealer and all our kicks come for free. Performance Consideration It's a t-shirt. Composition & Care 100% CottonWe source our cotton with almost zero environmental impact. Blog post coming soon. Machine washable at 30˚c Size & Fit Fits true to size. Order two sizes up for oversize fit. Delivery & Returns Free UK delivery. Free European delivery on orders above £200.