If you’re having trouble choosing a BCD, one of the factors you should consider is your body type. You need a scuba BCD that fits well because this device will give you the support you need in the water. Your body type will help determine what type of scuba BCD you choose. For instance, if you have a large frame, bulk won’t be an issue when you’re choosing a scuba BCD. However, if you are petite, you’d be better off with a compact scuba BCD. If you are short-waisted, one way to ensure a good fit is by selecting a scuba BCD that has an integrated weighing system. Consider the length of your scuba BCD. You don’t want one that extends too far down because it will make removing your weights more difficult. Choose a model that fits snugly and doesn’t ride up your body or one that has a customizable fit.
The jacket style is perhaps the most common type of BCD among divers for the last 30 years. The BCD consists of a wearable sleeveless jacket into which an air bladder is integrated that wraps around the diver. The types and configurations of this kind of BCD are numerous, but the basic premise remains that the bladder wraps around and inflates both in front, on the sides, and behind the diver. The jacket-style BCD is very comfortable and provides pockets for storage and is commonly found with pouches for weight integration which replaces the need for an independent weight belt. Jacket BCDs are extremely stable in all positions in the water and are the most popular choice for recreational divers all over the world.
The back inflate BCD only has an air bladder on the back, leaving the diver’s chest area uncluttered. Back inflate BCDs are known for how great they are at positioning the diver in the more flat horizontal position in the water. Most divers strive for good horizontal positioning (trim). Being in a nice horizontal position is very streamlined with the diver having less resistance moving in the water while swimming; this reduces workload and helps to prolong your air supply. Like the majority of modern BCDs today they are virtually all weight integrated, eliminating the need for a cumbersome weight belt. Some divers when used to diving in a traditional jacket style BCD find the transition to a back inflate BCD a little "different" when on the surface or vertical, however, this feeling soon passes, and the stability in the horizontal position while diving is truly appreciated!
The hybrid is described as "the best of both worlds" in terms of recreational BCD design. The innovative hybrid air bladder design allows less front clutter than most jackets style units and the flat horizontal diving position you get from a back-inflated BCD. However, the unique design allows you a more relaxed and comfortable vertical orientation when you find yourself in that position (kneeling on the bottom or on the surface).
The backplate and wing BCD is considered by many the most versatile of BCDs. There are unlimited possible combinations in backplate choice, wing size and design choice, and harness design and harness hardware choices when putting together a backplate and wing system. Most divers who choose this style will assemble to meet their specific needs, often with their instructor or mentor. The Backplate and Wing system is a great choice for divers who are contemplating moving into more advanced diving such as technical deep, penetration wrecks, or cave diving.
Sidemount systems allow you to dive with your tanks under your arms at your sides instead of positioned on your back. This style of BCD has evolved from Cave Diving in very tight areas to being a popular choice for many technical divers looking to move away from heavy double tanks on their back.