M Series
After the success of the "block" models Steinberger designed a more "standard" looking guitar, the M series. Buck's first M series is the GM1, which was designed by Mike Rutherford (Genesis) and his guitar tech.

The GM1 came with one pickup, and he had it retrofitted with an additional single coil in the neck position.

Buck also has several later models, the GM4-T and the stunning tobacco sunburst GM7-T, both of which feature the TransTrem, a Steinberger invention that allows you to transpose the guitar as a whole,in tune, in steps and half-steps in both directions. All total, Buck has 7 different M series guitars.

These guitars are still in Buck's collection.