I saw three competitors with modified belts. They used a ratcheting buckle to keep their belts together. You might recognize the ratcheting buckle system as it is commonly used on inline skates and ski boots. In the photo above, the shooter is wearing a Safariland ELS belt.
Most competitors run them so the two prong snap is positioned at the shooter’s back. That way they have uninterrupted real estate for mags and shotgun shells in front. One major drawback to using the Safariland ELS belt is the two prong snap design. It is very difficult to attach the belt on yourself. Too often I see competitors requiring the aid of another shooter to help fasten their belts.
With the ratcheting buckle modification it is much easier to secure the belt yourself as well as adjust it quickly. Readjusting a stock Safariland belt is not quick nor easy to do.
You can get these ratcheting buckles from ratchetingbuckles.com and they are not that expensive. I see they are around $11 for a buckle.