Does what it says
Before I start, I'm just going to say "Keep checking for the ball getting stuck". We have two bottles in our cage for this very reason and naturally, the day someone forgot to put the second bottle in the ball was stuck. Luckily I noticed pretty quickly and got it sorted.
On the other note it does leak a little bit when you first put it in and every so often afterwards, but nothing serious. The bottle is good value for money you just need to make sure little teeth can't get at the plastic while still being at a comfortable drinking height for them.