Buoyancy Control Devices (BCs) FAQ
Your choice as a diver is not critical because in-water the total weight difference is typically less than {4 lb}, so frequent flyers often choose aluminum over all other considerations when they want to travel as light as possible. For a more detailed discussion, see our tektip Aluminum vs. Stainless Hardware
About {25 lb | 10 kg} is the lift you need with your buoyancy aircell (called a 'wing') for single tank diving, assuming you are properly weighted with a modern cylinder. Manifolded doubles require about {45 lb | 20 kg} of lift. If you need more lift then you are diving a giant old Heiser/Beauchat cylinder or you are diving steel doubles with several stage bottles, otherwise you probably need to "get the lead out". These are just approximations because the cylinder sizes, types and configurations, not lift capacity, is the best guide to selecting the correct wing. We have more information in our article Suggestions for Selecting a Wing.
Most wings offer the option of a "Remote Exhaust" (aka pull-to-dump) elbow or "Plain" elbow. The standard pull-to-dump convenience feature is present on nearly all recreational sport BCD jackets and the default configuration on many single tank back inflation wings; the plain elbow is the default on most double tank wings. Experienced divers avoid the pull-to-dump feature, because it's difficult precisely control the amount of gas released and they do not like pulling on the inflation assembly. For experienced and technical divers, as a result of their often horizontal position in the water, they use the OPV pull to release gas or hold their inflation assembly above their head and press the oral inflate button to release gas. Many divers view the Remote Exhaust feature as an unnecessary feature that is just something that could fail and therefore prefer to use their skills to trade off convenience for reliability by selecting a plain elbow.
The standard corrugated hose on the inflation assembly is usually about 16-inches long. Some physically very tall or large divers need a longer corrugated hose length of 22-inches. Longer corrugated hoses are also usually found on BC integrated alternate second stage regulators. Some technical divers, especially cave divers, prefer a shorter 12-inch corrugated hose to reduce the "danglies".
The difference is primarily the fabric material of the outer shell and the warranty.
The EXP series wings have an outer fabric shell made of tough 1680 denier ballistic nylon. The EXP wings are available in black with gray side panels, and occasionally limited edition colors such as pink. EXP series wings feature a one year warranty.
The XT series outer fabric shell, built upon the SuperFabric® technology, is outstandingly rugged. Dive Rite's XT Armored wings have the durability of SuperFabric outer side with a 1000 denier Cordura® inner side to create an armor-clad shell that is impervious to damaging pinches, cuts and abrasions. The Dive Rite XT wings are available in solid black color and feature a LIFETIME GUARANTEE.
For more information visit Dive Rite Wings Overview.
Both are harness, backplate and wing type systems: The TransPac is a 'soft' plate using a semi rigid high-tech material. The TransPlate is fully rigid metal plate (your choice of aluminum or steel). With a properly adjusted harness, both are equally as stable. We are sometimes asked if the TransPac can have a plate "added"; the answer is no. While other brands do offer "hybrid" systems, because of the nature of the TransPac design combining hard and soft plates together wouldn't produce any benefit. The hybrid systems offered by other brands can best be thought of as a TransPlate with a lumbar backpad option.
We most often recommend the TransPac because it is always more comfortable and form fitting than the TransPlate. Even adding a lumbar backpad to the TransPlate will not make it as comfortable or form-fitting as the TransPac. If you want to add extra weight, choose the stainless steel TransPlate system. Most people diving double cylinders choose the TransPlate. Most people diving single cylinders choose the TransPac. Most people who dive drysuit exclusively choose TransPlate, most people who dive wetsuit exclusively choose TransPac.
The simple answer is "probably not". The STA is a product which predates modern backplate and wing designs that include pre-cut slots for cam straps. Using the straps threaded through the backplate snugs the tank and wing up very tight against the backplate and does not allow the tank to rock. Using an STA sets the tank farther away from the backplate and allows the tank to rock slightly by pivoting from side to side on the bolts. For more information read our article Single Tank Mounting with Backplaces.
Assembly screws are also called "book screws" or "sex bolts", and are available in both metal and plastic versions. Years ago our suppliers used to include a metal set with their wings and later switched to a plastic set, but have not included either for a long time because most experienced divers don't bother to use them.
The plastic assembly screws can be used to attach the wing directly to a hard metal backplate when rigged for a single tank without a single tank adapter. Note that this function is just cosmetic, omitting the assembly screws does not cause a problem. Without the assembly screws, when the BCD is taken off a single tank, the wing will hang loose on the cam straps.
The metal assembly screws can be used to attach accessories to the holes on edges of metal backplates, but in our opinion the plastic ones actually work better. Don't be concerned about the strength of plastic vs metal; the plastic version is plenty strong for these applications plus they are not subject to galvanic action and don't cause wear on materials rubbing against them.
