The RM-20, RM-40 and RM-BS rack mounts are screwed to the side of your TubeMeister Deluxe 20 or 40 or GrandMeister Deluxe 40 or Black Spirit 200 to turn your amp into a ready-made (4 HU) 19" rack unit. Be careful though: the hot tone of tubes needs cooling! We recommend building your amp into a rack only if you have sufficient cooling and ventilation (except when using Black Spirit 200). Commercially available 19" cooling fans from the world of home computing are well suited to this purpose, for example the PROCOOL HK640B, which was custom designed for Hughes & Kettner: www.procool.com
Note:
Amp, rack and rack fan are not included.