The Dunnett R-Class 10.5mm Rail Mount lets you attach a tom directly to your converted floor tom, letting you fashion your own club kit for those gigs where a full-sized drum set is too much, as long as your floor tom legs are 10.5mm in diameter.
How's it work? Your converted floor tom should be sideways, with several empty leg brackets that aren't being used. On the rail mount, one of the rods has a rubber tip - slide the opposite end of that rod into the empty floor tom leg bracket.
The rubber tip should then lie easily on the shell of the drum, and the L-rod on the other side of the mount will be pointing upwards, just waiting for a second tom to be mounted. This mount is also angle and length adjustable, for the perfect fit.