TravelCoat® كانون 600 f/4 IS II/III

The 3mm neoprene is plenty thick—I can feel the shock absorption just pressing on it, and it slides over the barrel in seconds without any wrestling. It's snug enough that I trust it in a packed roller bag next to a tripod head.

I usually shove my 600mm in a backpack with other gear, and this cover slides on easily without fighting the hood. The custom fit keeps it snug against the lens body, which saves me from worrying about bumps during travel.

The closed-cell neoprene padding has a nice, solid feel—it's clearly built to absorb a knock without adding much bulk to my bag. Slipping it over the lens takes about two seconds, and now I stop worrying about the gear rattling around.