On the outside of the rain cover towards the bottom there are two smal black plastic grawments, it apears that someting attaches or spreads the cover ????

Tech Specs:

Material:

210D PU-Coated nylon 

Pack Size:

(XS) 1000 - 2000 cu in, (S) 2000 - 4000 cu in, (M) 4000 - 5000 cu in, (L) 5000 - 6000 cu in, (XL) 6000 - 7000 cu in 

Weight:

(XS) 3.2 oz, (S) 4.1 oz, (M) 4.8 oz, (L) 5.9 oz, (XL) 6.5 oz 

Recommended Use:

backpacking in wet weather 

Manufacturer Warranty:

lifetime