The pakajak is a no frills windproof shell that does as it says in the title packs down into a tiny stuff sack included so you can carry it with you all the time ensuring it is there for when you need that extra bit of protection to keep you comfortable'. '.strtoupper('w')eather ready protection the jacket is constructed using a lightweight windproof ripstop melange fabric with a pfc free dwr treatment'. '.strtoupper('t')he underarms use an open mesh to improve ventilation and comfort'. '.strtoupper('c')onsidered safety reflective trims on the front rear and sleeves increase your visibility to other road users'. '.strtoupper('t')he high viz yellow option adds an additional layer of safety in low light conditions'. '.strtoupper('u')ltra lightweight and windproof ripstop melange fabric laser cut bonded stormflap reflective trims on sleeves shoulder and rear underarm mesh vents for enhanced breathability simple neat elasticated cuffs and hem tiny pack size stuff sack included nylon 100% polyester 100%