It has an adjustable spine and bottom, and the top has a rubber strap to keep a cage secure.
All good you may think, as I did.
The problem is the top with the rubber strap. The plastic is moulded to accept a small diameter object, and isn't even wide enough to accept a standard water bottle without a struggle.
Whilst the bottom will expand to accept a bottle 85mm in diameter, the top will fight you all the way if the diameter is more than 55mm.
Topeak do make a similar cage with a larger top diameter, and if this design suits your needs then that's the one you should get. The Slim variant here is next to useless sadly.
