A pair of 2N6308 are used as Q1 & Q2 on the main board in the "DataPower" variant of the Lisa Power Supply, often referred to as the "1.8A" PSU due to the rating label.
This component does sometimes fail, but is not often a problem.
These transistors drive the rectified mains power through the primary side of the main transformer in a push-pull manner, controlled by the SG3524 on the daughterboard.