Rab Xenair Light £150

Excellent as a mid layer, very lightweight, breathable Not the warmest, no hood

Rab’s new synthetic Xenair range features three models: the Xenair Alpine, Xenair and Xenair Light. The latter is the lightest (and cheapest) of the trio, and it works better as a streamlined mid layer than any others on test. This is because the synthetic fill is like a sheet of flat, low-profile, wadded insulation, rather than a plumper, loftier, cluster-like fill in baffles. Consequently the Xenair’s bafflefree design and flush-to-the-body cut fits more comfortably underneath a hard shell. Another nice feature are the thumb loops on the stretchy wrist cuffs.

The jacket is the lightest here (264g) and has been carefully designed to improve breathability, enabling it to be worn all day even when active. PrimaLoft Gold Active+ insulation aids climate control; body mapping means there’s no insulation across high-heat areas including the armpits and sides; and the Pertex Quantum Air shell’s ‘open woven structure’ allows air to flow through it freely.

The trade-off for all this breathability is that the Xenair Light is far from the warmest. It might prove insufficient on sub-zero days, necessitating carrying extra layers, while wind-resistance isn’t the best.

■ Insulation PrimaLoft Gold Active+ synthetic insulation with 55% recycled content, 40gsm

■ Sizes: Men’s S-XXL Women’s 8-16

■ Weight 264g (men’s S)

Verdict

An ultra-light jacket that works excellently as a mid layer – but too thin for colder conditions.