Scuba BCDs - Vest Style BCDs
Vest BCDs
Vest BCDs are typically for warmer water and more experienced divers. The inflation bladder is behind you. In many ways this is more comfortable as there are no bladders in front to constrict movement.
They are usually for more advanced divers because obtaining balance and neutral buoyancy is a bit of a challenge because inflation is to the rear
Many divers find the rear inflate BCD helps them stay horizontal when they are on the bottom. Coupled with the fact that the front of you is unrestricted, this is a great option for more advanced divers.