There is a hole for a water bottle spout but not the wire holder thingy, also the hole is too high up for a hammy to get to unless you put something under it for them to climb onto so they can reach.
I got the ferplast sippy bottle that comes with a holder and the holder has suction cups, I hated the bottle so threw it away. I then got a regular water bottle, attatched it to the sippy holder using and elastic band and then sucked it to the inside of the zz!!
Other people have these.....
The Pet Express - Wooden Chew Cube - £2.99 - Small Animals - Feeding
Take the fluffy bedding out, and pop the water bottle in the top hole and the spout will stick out the side hole