Class E VPS protein implicated in concentration and sorting of cargo proteins of the multivesicular body (MVB) for incorporation into intralumenal vesicles. The lumenal sequestrated membrane proteins will be targeted into the vacuole after fusion of the endosome with the vacuole. Acts a component of the ESCRT-III complex, which appears to be critical for late steps in MVB sorting, such as membrane invagination and final cargo sorting and recruitment of late-acting components of the sorting machinery. The MVB pathway requires the sequential function of ESCRT-O, -I,-II and -III complex assemblies. Required for the oligomerization of SNF7 into a membrane-associated filament. The VPS20-SNF7 subcomplex is responsible for the membrane association of the ESCRT-III complex. Also required for the RIM101 repressor proteolytic activation. Core component of the ESCRT-III complex (endosomal sorting required for transport complex III). ESCRT-III appears to be sequentially assembled as a flat lattice on the endosome membrane and forms a transient 450 kDa complex that contains DID4, oligomerized SNF7, VPS20 and VPS24. SNF7 oligomerization into a membrane-associated filament is nucleated by association of SNF7 with VPS20; the process is terminated through association of VPS24, possibly by capping the SNF7 filament. VPS24 subsequently associates with DID4/VPS2. Interacts with the VPS4. Interacts with VPS25; the interaction mediates the association with the ESCRT-II complex. Present with 937 molecules/cell in log phase SD medium. Belongs to the SNF7 family.