Hi, they are very nice and as IMR has already said, if the edges are smooth which they seem to be and there are no sharp edges, then Pleos should be fine, I have many pleos, and for photos, special occasions, I sometimes put a necklace on or something that I ordinarily would not. Only because Pleos can move in strange ways, esp Pleo rB when hatching or very young can move necks and legs almost together and a necklace could get caught up in that area, though they would have to be in a sleeping postion, I otherwise use a soft homemade necklace or bandana, anything soft. If you have only one or perhaps two pleos then you are less likely to have any problems.
They are very nice. Be sure to show photos of your pleo wearing them when you get the chance. RWM
and the Pleo township of the REdwoods