The Ultra-Sil Pack Cover ends the debate about whether you should carry one or not. It's a tiny and compelling solution and the medium size weighs less than four ounces. Plus it packs into its own small stuff sack - why wouldn't you carry one?

Features
Made of 30D Ultra-Sil™ fabric constructed from CORDURA® yarns for durable, waterproof performance.
This pack cover does not use seam construction to ensure that it is completely waterproof
Packaged in its own mini siliconized Nylon stuff sack that remains attached to the cover so it can't get lost
Keeper strap (sizes S-L) pulls the pack cover tight across the pack harness
Sold in four sizes to fit daypacks up to large backpacks