There's debate on where the heat pack should go. Linda Olson (transhipper in the US) puts them under, however the heat pack instructions say to place them on the box lid. I've done experiments with them and TBH it doesn't matter where it goes as long as it never comes into contact with the fish bags.
Who am I? Well I am a Junior Member of the International Betta Congress and a breeder of white HMPKs, red dragon HMPKs, black/red dragon HMPKs, metallic multi HMPKs, blue masked HMPKs, and now multi color HMs. Soon to add black HMs. I will be showing in New Breeder class in fall of 2012.