Mountain Equipment’s Helium 400 Long is a superb sleeping bag. Lightweight, versatile, and packable, it is perfect for backpacking and bikepacking adventures. Insulated with 700-fill duck down: the box wall baffle construction and Alpine Fit 2.0 maximise thermal efficiency. A solid three-season performer, it gives the warmth needed for the cooler nights experienced in late spring and early autumn. Ideal for taller users, this Long version has a maximum user height of 200cm.