Mammut's Masao Light HS Hooded Waterproof Jacket is a very functional hard shell with decent breathability and a low weight. The jacket doesn't have the clammy feel on the skin you get with some hard shells. Pit zips aid venting when working hard.
The pockets are positioned so you can use them when wearing a harness and and the zips are water resistant. A flaw is the tiny zip pullers which would be very hard to use with gloves. The cuffs are half elasticated to give a good fit. There is adjustment on the hem.The peaked hood can easily accommodate a helmet and 1 simple drawcord adjuster can cinch the hood to size.
A nice touch is the supplied stow bag with clip in point so jacket can packed away tidily when not in use.