"Developed by La Bella's president Richard Mari Cocco with Ned Steinberger, these strings have been manufactured to exact specifications for Steinberger's revolutionary headless instruments. The La Bella company are the legitimate makers of these patented Double Ball System strings which are specifically required for guitars and basses by Arbor, Burnside, Cort, Hohner, Lotus, Mach I and Status. Steinberger S Series Double Ball guitar strings may be used for the 'Transposing-Tremolo' model guitar, however, for the best results we recommend the ST or STP Series calibrated sets."