The Schaller Bass Bridge was used on just about every Kramer Pioneer bass from 1981-1986. It was stamped with Kramer on the bottom of the bridge. Other Schaller bridges of this type have surfaced with other engravings in the bottom, but typically the Kramer stamp appeared on most Kramer basses.

The Schaller bridge was presumably dropped (reference: late 1987 catalog) for the Spector bridge on the Forum bass line. The bridge was mostly seen in gold.