Yep, the gents above are correct. Maxamps do a hard case that is shrunk onto the packs (with a removable version). Also, they are no bigger than 3 cells so should fit any saddle pack config. I've been using Maxamps packs for ages and they are absolutely superb batteries with phenominal service. Highly recommended.
I wish more info was available on the Trackpower hard cased saddle packs but I've seen nothing yet.
