I've had multiple shoulder separations/dislocations, had them surgically reconstructed twice, and recently dislocated/separated my shoulder again. Just walking around hurts and I can't hold more than about 5 lbs before my shoulder subluxates without a sling or brace. I've tried numerous braces and the SB03 is the brace to get if you've got shoulder dislocation, subluxation, separation, torn rotator cuff, and/or damaged ligaments & tendons as it provides effective support and preserves enough range of motion to still be functional. I find this brace significantly more comfortable and supportive than even a sling. The brace is constructed of neoprene and you will sweat if you are exerting yourself at all so I wear a t-shirt under it. I appreciate the adjustable arm closure: as other reviewers have stated - it might need readjusting if you are using arm muscles much or wearing it for long periods. The construction is much heavier duty than typical shoulder braces. The body/straps/x-brace are all made of heavy neoprene to which velcro will stick everywhere. The strap ends are all heavy duty velcro with rubber covers (the rubber covers are on the front and back sides of the chest strap closures and all four ends of the x-brace straps). The rubber covers are thick enough that you will notice them if you lean or lie against something firm. If you have shoulder pain/instability to appreciate this brace, you will look at any such discomfort from a hot brace with firm closures as a small price to pay for the joint support. If you've got two bad shoulders, it is possible to wear two of these braces - keep in mind that the overlapping chest straps would be akin to wearing an 8mm wet suit so your upper torso would be toasty and well supported. I'm borderline L/XL according to the size chart: around 6', 200lbs, with a 34" waist and a 43-44" chest measured around the ribs just under the pecs (usually wear a 44-46" jacket). I found the size Large to be just big enough, tight and supportive. I have the pecs of someone who benches a lot and the girls in my fitness classes regularly joke that I'm a A- cup size. You will find one side of the wide chest strap is firm across the chest (acting to flatten/pushup) and the other side has a triangle shaped cutout that your pec will stick out (providing firm support everywhere but the 'cup' area). If I was female with a larger cup size, I can't imagine something designed to provide more lopsided chest support and I'd likely invest in very supportive sports bras if I needed the relief of this shoulder brace. I've found the braces that have a single chest strap are not nearly as supportive but can usually go above the chest. The brace can be worn under dress clothes and is very supportive for manual labor, walking, running, biking, and weight lifting. It holds the shoulder firmly in the socket and still provides for some overhead motion. It is possible to play racquet sports, basketball, volleyball, and throw while wearing the brace but it does restrict motion somewhat. If you have enough shoulder pain/instability to require such a brace, you probably won't think it's too bad. I don't think you can find a brace that is supportive and completely unrestrictive but the x-strap is somewhat adjustable, enabling some tradeoffs in support and motion. Once adjusted, the brace can be slid up the arm, rolled over the shoulder, and put on/off using only the chest strap velcro closure. You may want to avoid tearing the velcro apart and instead gently peel it off to minimize wear on the hook/loop closures. One reviewer suggested flipping/reversing the chest strap closure to distribute wear and I think this is a good idea monthly. The neoprene gets sopping wet with exertion and I air-dry it daily and run it through the wash weekly on the gentle cycle in a mesh bag (to avoid it getting stuck to other clothing). This brace works well enough that I'm considering putting off another shoulder reconstruction despite my complete AC joint separation and continued issues with dislocation without the brace. Surgery has been very effective for me in the past, but the first few months of recovery from surgery are rough and it wasn't until about 12 months of really hard rehab that I started to enjoy the benefits of surgery. This brace allows a pretty active lifestyle and I'd even wear it at night if I had trouble sleeping on my back. The SB02 is the same brace but without the x-strap and is significantly less supportive, but with less restrictive motion - you can remove the x-strap from the SB03 so I don't think I'd buy the SB02 unless I needed a second brace for light support: perhaps sleeping or under dress clothes. The SB04 is the same as the SB03 but the x-strap has a padded hard shield. The hard plastic shield of the SB04 can provide firmer compression of the shoulder joint if you need more support than the SBO3 but your satisfaction with it will depend somewhat on the shape of your shoulder as the shield is not very flexible. I'd recommend the SB04 if your shoulder is sensitive to impacts and you are doing dirtbiking/motocross, bmx, mountain biking, horse riding, or some form of martial arts/contact sports. Otherwise you probably don't need the SB04 unless the SB03 isn't supportive enough for you. The SB05 is a double SB02 (to which you could add the x-strap from the SB03 or shielded X-strap from the SBO4). The SBO2/SB05/SB03 can be worn under football shoulder pads without too much discomfort (you might notice the rubber velcro covers more with shoulder pads over top of them, particularly the upper x-strap ends), but the shield on the SB04 would be like having an extra hard pad under the shoulder pads.
