Nuyarn Technologies has partnered with Arizona-based trail running apparel brand Unknown Runner to launch a new ultralight merino performance collection designed for trail running and outdoor activities.

The new Courser Collection features a lightweight 115-gsm merino blend fabric developed for warm and changing weather conditions. Made from 63% merino wool, 29% polyester, and 8% nylon, the open-knit fabric is designed to provide natural temperature regulation, effective moisture management, odour resistance, and next-to-skin comfort while remaining lightweight.

The collection is built using Nuyarn’s proprietary drafting technology, which wraps merino fibres around a nylon filament instead of using traditional high-twist spinning methods. According to the company, this process produces a yarn that is lighter, dries faster, and offers significantly higher durability. Combined with a polyester knit construction, the fabric is designed to maximise breathability while maintaining reliable performance during demanding trail running activities.