Brake holder for Avail tuning spools.
MT07: Avail spools for Shimano Metanium (Chronarch 100) '92, '97, '00, '05, '07 reels, Scorpion XT1500
ALD09: Avail spools for Shimano 09Aldebaran MG
CNQ50: Avail spools for Shimano 00 Conquest 50, TE50
These brake holders have smaller hole than stock spool's, and you may fit these by drilling the center hole.