I had been looking for a nice quality padded case for once-owned Gitzo G1588 Monopod with a Wimberley Quick Release Clamp mounted. I thought the Gitzo Padded Tripod Bag GE10P might be the answer. Unfortunately, the GE10P is about .5" too short for that specific application. It does however work very well for the newer Gitzo GM5540 Monopod with a Wimberley Quick Release Clamp attached.
The Gitzo Padded Tripod Bag GE10P also proved to be perfect (snug) for my once-owned Gitzo G1128 / Arca-Swiss B1 Ballhead combination. It makes a compact setup for hiking and travel.
The Gitzo Padded Tripod Bag GE10P measures 20 7/8" long by 3 7/8".
Here is general information about Gitzo's Padded Tripod Bags ...
It is not hard to get a significant amount of money invested in quality tripods and ballheads. You will want to protect your investment with an equally high quality tripod case. Gitzo padded tripod bags are made from a tough nylon material that Gitzo refers to as rainproof. Padding adds to the protection. Access to the bag is provided by a double-zipper. A small zippered pouch inside the bag can hold a remote release and other accessories. A double handle provides strong support and a shoulder strap makes transporting a tripod easier. A Velcro-covered luggage tag allows identification.
I recommend using Gitzo's dimensions to find the proper size case (models GE10P through GE15P) - not their recommended tripod fit.