An apparatus includes a laminated bus bar assembly with first and second bus bars and an intervening insulator layer. A surge arrestor (e.g., a metal oxide varistor) has a body mounted on the bus bar assembly and first and second terminals on first and second opposite sides of the body. In some embodiments, the body may be at least partially disposed in an opening in the first bus bar and the second terminal may be conductively bonded to a surface of the second bus bar that faces the insulator layer. In some embodiments, the second terminal may include a conductive stud passing through an opening in the second bus bar. The apparatus may include a spring clamp attached to the first bus bar and contacting the first side of the body to retain the body.