Built for streak storm insurance, the 100 waterproof, super-breathable Helium II measures an amazingly light 6.4 ounces. A ultra-compressible piece you’ll never abandon, it’s so light and packs down so little you’ll overlook it’s cut to your saddle until the point when you divert it on to ward from a sudden mid-course deluge. Compressible to the span of a granola bar.