Belt are another thing to decide on if you are going to be using a hyperbaric chamber, especially important if you are going in alone without someone on the outside zipping you in. The belt models are cheaper but they take more time to get in and out of.
Note: I have been reviewing chambers for about 3 years and the companies that sell the non-belt/ buckle chambers talk how theirs is better and the ones that don't use straps and buckles say how the ones that have to have the straps use them for added protection because the thickness and weight of the chambers are much lower and cheaper to build. So far, the leaks and customer complaints are usually from the misuse of the chamber and on aged chambers that need to be repaired naturally over time.
The belts are good if the chamber is going over 4 psi and is not really a safety issue if under that. The most expensive portable chamber on the market, around 27,000 dollars, has the most belts and buckles of all. It even has a double bag too.
The buckled chambers are cheaper but they are heavier to transport. Most people want the stainless steal buckles. They are heavier but the plastic ones are not as desired. If keeping the chamber and not transporting it, then steel buckles is usually preferred. The plastic ones are lighter but also have their cons as well but the main pro being lightweight. The steal ones can hurt if they hit a patient in the head when getting in. You learn to quickly tuck them back as you get hit enough. One hand has to lift up the chamber air release valve and oxygen lines connect there on the top.
One thing for sure, the belts make the zipper last longer, especially if the chamber has plastic zippers and a low tooth count. If you are going to get a chamber with out belts, make sure the zipper track is wide and the tooth size is large. The larger the better so it does't need to be sent in for replacement or refurbishing.
Buckle Number: More is always better if you want it to last a long time and take stress of the zipper. Some have as many as 7 straps and as low as 4 straps.
You do have to fasten EVERY buckle. A person must reach reach towards his or her ankles to fasten the furthest buckle in ... of the first strap and buckling this first strap prior to entering the chamber.
Buckles Grade: Some are aeronautical grade stainless steal buckles and other are just regular
stainless steal types. The aeronautical grades are the best but also the most expensive to put on the chamber. Just like on cars, some seat belt buckles are easier to snap and others aren't.
Basically, their are pros and cons to buying a chamber without buckles or ones that don't have any belts or buckles. About 50 percent of the people that buy chambers get the strapless ones and the other people get the buckled ones. It's usually a matter of expense. The most expensive chambers that are used in the clinics do not have straps. Some people don't mind taking the extra time to buckle someone in or themselves. Some people hate buckling themselves in and don't want to spend an extra second to do any extra work. The buckled ones are about half the price of the non buckled ones. But the, double bag types that have the most buckles, cost the most, even more than the non buckle types.
If you are debating on which type to get, and don't want to get stuck with a type that you don't like to use, please take my hyperbaric chamber quiz. I will help you pick out the type based on what your answers are. I will contact you if I need to. I suggest trying each type first always. If there is someone in your area that has one to let you try, I will let you know. This is the biggest decision of buying a chamber. It's like buying a car and deciding if you want automatic or stick.