I know hand warmers get hot - but if I put one under the bedding material in the shipping box so the chicks would not touch it directly - maybe put an extra layer of the bedding materials - would it work? I need to ship chicks tomorrow - but the weather has turned cold. I could order some of the warmers made for shipping pets - but it would take days to get them - and I need to ship the chicks tomorrow. Anybody know about this?