The Compressor Hooded Jacket is very similar to the M.E. Arete Jacket. They are both considered as a heavyweight mid layer piece or a super lightweight belay jacket & both are constructed using the same Helium 30 outer fabric; however the Compressor is filled with Prima Loft Gold instead of duck down. This means that this jacket is more suitable for use if you know the day is going to be wet (which in the UK are most days); the reason for this is because Prima Loft Gold still works when wet where as a down would just die. The Helium 30 fabric itself is highly windproof protecting the nice warm air that is trapped within the Prima Loft insulation. The adjustable Mountain Hood gives a precise cranial fit & like any decent belay jacket; it packs into its own pocket & can be attached to your harness using the stitched in crab loop. Helium 30 outer is exceptionally lightweight & windproof Prima Loft GOLD insulation [60g with 40g arms & side panels] Quilted body construction Adjustable Mountain Hood 2-way YKK moulded centre front zip 2 zipped hand warmer pockets Napoleon chest pocket For all you kit geeks out there, the links below will take you to Mountain Equipments Information pages where they will explain this jackets different fabrics, fills & constructions techniques in greater detail. Helium 30 Polarloft Duo Mountain HC Hood Dual Tether Hem Drawcords Most people are scared to wash their down jackets but like all equipment it does need to be maintained. It is actually really easy! Feel free to give the shop a call from 09:00 until 17:30 Monday to Saturday (19:30 on a Wednesday), as we are always happy to help & give friendly advice. Or if you are reading this outside our normal opening hours here is a useful link to Trekitts recommended product for washing & caring for kit. Nikwax Tech Wash Nikwax TX-Direct I hope this helps.