Crystal oven model SA-2-41. Has crystal sockets for two (2) HC-6/U xtals. Heater element operating voltage 12.0VDC minimum and 24.0VDC maximum. Maintains oven cavity temp rating of 75.0 degrees celsius. Mounted on plug in eight (8) pin standard tube base. Has a removable outer casing. Spec sheet included. $29.95 includes shipping. J W7KSG