Mild weather hiking and trekking usually involves unpredictable mountain weather.  And that is where the Zeta SL Jacket enters the picture. Designed as an emergency shell for hiking, this is also great for around town in an urban environment. It packs up small so it's ready whenever sudden inclement weather arise, and is superlight and breathable. The minimalist design and fully articulated patterning gives an exceptional fit and freedom of movement, while the adjustable cuff and hem help seal out the weather.