The backplate and wing are two separable components of a scuba harness. The buoyancy compensator attaches both pieces to the buoyancy compensator. This creates positive buoyancy at the surface and neutral buoyancy under water. Each component can be separated from the other. Backplate and wings are modular systems. They can be a great choice for divers who don't know which type to choose. These are the pros & cons of each.
Stainless steel
You can have your stainless steel wings or back plate with or without a belt. 316 stainless-steel is used for the backplate and wings and is highly resistant to saltwater. The strap is manually polished and cut using a CNC cutter. They can also be used in conjunction with single-air-tank or dual air-tank systems. For easier storage, the wings and backplate can be removed from stainless steel.
Aluminium backplates weigh more than stainless steel. Stainless steel backplates are great for colder climates, where they'll reduce the weight you'll carry during your dive. Stainless steel backplates, unlike lead pieces, can be easily adjusted to fit most diving tanks. A Halcyon Dealer can provide weighting advice to determine what's appropriate for your body weight. You don't have as many to replace the backplate.
Plastic
Although the plastic back plate/wing buoyancy is not ideal, it can still be useful for replacing weight on the weight belt. Jacket BCDs have pockets and weight integration. These features are not present in the backplate or wings system. These components can be ordered separately. Both are available separately. We'll discuss the pros and con of each. It is vital to select the right backplate for your needs.
Softpack harness
There are several types of harnesses that can be used for the wings and backplate. The most popular are wing BCDs (backplates) and wing plates. They come with all the components needed, including a harness and backplate. Softpack BCDs make technical divers' lives easier. They are lightweight and flexible and do not attach to rigid plates.
The drawback to steel backplates harnesses is their inability for adaptability. The harness is not intended to be used with single tanks. The steel harness is rigid but can be difficult to use when traveling. It is not suitable for single tanks and the steel backplate might be too heavy to use on the ground. This can be modified to work with single tanks using adapters but it is not recommended.