Glass looks like an odd material to hang inside a hutch, right up until you have replaced the third plastic bottle in a year. Plastic clouds, then it scratches, then an animal with continuously growing teeth decides the spout is a chew — and you usually find out at the point the bedding is already soaked.

Classic make these in recyclable glass, which is dishwasher safe, with a metal spout and cap unit they say makes the bottle chew proof. The valve is their original double ball bearing design, which they say is what keeps it leak-free. There is a carrot-shaped float so the level can be read at a glance, and capacity graduations up the back of the bottle for when you want to fill to a set point. It hangs on a cage at two separate points, through a spring clip and a hook bracket, and comes in capacities of 175 ml, 350 ml and 750 ml.

• Three capacities: 175 ml, 350 ml and 750 ml
• Recyclable glass body, dishwasher safe
• Metal spout and cap unit, described by Classic as chew proof
• Double ball bearing valve, which Classic say gives a leak-free bottle
• Carrot-shaped level float, plus graduations on the back of the bottle
• Fixes to a cage at two points, with a spring clip and hook bracket

On picking a capacity. Classic name the 750 ml as suitable for larger rabbits and guinea pigs, and for birds such as pigeons and parrots. They publish nothing equivalent for the other two, and no external dimensions for any of them — no height, no diameter — so if your cage bracket has a fixed span or your hutch has a shelf above the drinker, measure the gap before you choose. The other trade-off is the obvious one: glass will not be chewed through, and glass breaks if it is knocked onto a hard floor.

Who it's for: rabbit, guinea pig and bird keepers who have already lost a plastic bottle to teeth, and anyone who would rather read the water level from the doorway than unclip the bottle to check it.