Floor tom rim mounts may be attached to a rack, or provide places for the three traditional floor tom feet to attach.
Bulkier and heavier than traditional mounts, they generally require drum cases one size larger.
The earliest rim mounts were developed by Gary Gauger and first became available in 1980 as aftermarket accessories, under the registered name RIMS, standing for Resonance Isolation Mounting System.
It was more than ten years before major manufacturers began to offer them as an extra cost option.
These days they are offered by most major manufacturers, and common on high-end kits, particularly for high-volume situations.