There are three strap change mechanisms.
Screw-in - Need a 1.6mm screwdriver
Quick release - Need the plastic tool that splits into two (or in a bind, a toothpick broken in two will do just fine)
Springbar - Need a springbar tool
All three function like their gen counterparts. Ask the TD what strap change the rep you will buy uses if it's not obvious (I don't have a PAM904 so I can't say but it looks like a screw-in). If you're lucky and ask nicely, maybe he might even include a screwdriver with the watch.