Mountain Equipment's Superflux Insulated Jacket is a great mid weight synthetic jacket with just the right amount of features balancing functionality with weight saving.
Mountain Equipment says:
Superb all-weather insulation combining wamth, breathability and protection in a single versatile layer
POLARLOFT® Featherless insulation not only works wet or dry but, thanks to its blown construction, breathes effortlessly as well. Combined with our highly protective DRILITE® Loft outer the Superflux is a jacket that thrives as an outer or mid-layer in the most difficult mountain conditions.
Mountain Equipment's Superflux Insulated Jacket is a simple and effective jacket. The Polarloft featherless insulation mimics down with great insulating properties but retains its warmth when wet unlike down. The Drilite 20 Loft denier is durable, completely windproof and very water resistant.
Feature-wise there's a generous sized internal chest pocket and 2 large hand warmer pockets, one of which doubles as a stuff sack with integrated carry loop. The hood is elasticated for a close fit and can be cinched in further with the drawcord on the back. The elasticated wrist cuffs and drawcords on the hem ensure you get a close a fit to help keep the heat in and cold out.