Sorta like a round Speed Strip. Instead of the rims being fully encirled, they are open between the 4 0'clock and 8 o'clock on the bottom so that you can slide the shells into place. Tension is provided by what looks like spring steel C-clips imbedded in the rubber body of the loader. Rounds are staggered in pairs instead of being equally positioned as with other designs.
Consider the face of a clock as I try to describe this.
When you hold onto the ring, and position the loader over the cylinder, the rounds at the 4 and 8 enter the chambers first. They project furthest outward from the loader and are seated totally up to the rim. The 9 and 3 shells follow, and remain out further, with the 10 and 2 rounds ending up about 1/2 way in. This all occurs in one motion just as with any other loader. Then, you
peel the loader toward the 12 o'clock by pulling upward on the ring. Just like you peel off a pair at a time with a Speed Strip, only all six are done at once.
Obviously, you must orient the cylinder and the loader so that you are not attempting to peel the ring toward the gun. Traditional units don't require this. How well the little tension rings will hold up under use is unknown, what with the whole unit constantly flexing and stressing. Many competitive shooters keep the gun in the strong hand and load with the weak hand without supporting the cylinder at all. IMO, the effort exerted in using the Maxfire would put undue stress on the crane with any such technique.
All in all, they are an inexpensive trial-and-error if you find that you don't care for them.