The "rolling hay ball" is very pretty, but, it has some plastic in it's design. Plastic is never good for a chinchilla.
Considering buying a bird suet cage holder and lock it with a small dog clasp from a leash. To hold their hay...I need something in there to hold it...But nothing that will put my fellas in danger.
A word of caution here ... please get the one that is not covered in a plastic/rubber coating ... the chins will often eat the coating which can cause health problems.
There are many other options. A hay bin, "J" feeder, there are hay holders made of many different shapes and sizes. I will post pictures of some that I have come across over the years that I, personally, think are safe.
Many can be homemade.
Bending cage wire [1/2" x 1/2"] into an "L" shape and attaching it to the upper corner or a vertical corner of the cage and can be used as a hay holder.
OR Bending cage wire into a U shape can be attached to the side of the cage and used as a hay holder.
These two are best used with cube hay ... they get a little messy with loose hay. The least messy place to attach the "U" shaped holder is the very top of the cage ... but this can be a bit awkward to fill.
Jo Ann
The "J" feeder is much like the regular pellet feeder, but does not have the solid side that fits next to the cage to prevent pellets from falling into the cage.
The one in the first photo is a cube shaped holder ... caution with this one is to always make sure the "lid" is securely attached each time you fill it.
The second picture/feeder is the safest I have found ... I use only this kind and the open "J" feeders.
The chin swing, the last one shown, could also be used as a hay holder.