The short version replaces a string stop style tailpiece, such as found on the original Gibson Les Paul, and transmits the string tension to the guitar belly, so short versions are generally used only on solid body guitars. Long tailpieces can be used on almost any guitar (an exception being the Gibson Flying V where there is no room for one), and both long and short versions have been used on various models of Gibson SG and Gibson Les Paul guitars. The Gibson designs were less suitable for the sounds that the Stratocaster tremolo and its derivatives made possible. They have almost always been offered as extra cost options on guitars that sold better in non-vibrato versions. As a result, some versions are rare and command high prices from restorers and collectors. Gibson encourages this trend by refusing to sell reissue units as parts, offering them only on complete guitars (a policy similar to most guitar manufacturers). Gibson was continuing to offer Vibrola units as options on many models, but also offered a few Fender-inspired tremolo arms such as the Floyd Rose on some Gibson branded guitars (Nighthawk, M3), and a wider variety through their Kramer and Epiphone brands. Kramer have always fitted Floyd Rose trems as standard and this association continues. Other designs Other notable vibrato designs include the Kahler, Washburn Wonderbar, Hagstrom Tremar, The Semie Moseley-designed Mosrite "Vibramute", the Stetsbar, the crossed-roller bearing linear tremolo and the early Rockinger from Germany. This last company was contracted by Kramer to develop a new fine-tuning tremolo with Edward Van Halen. The Rockinger designs proved problematic and Van Halen ultimately came to favor the Floyd Rose tremolo. The Mosrite Vibrato Semie Moseley developed the vibrato unit used on his Mosrite guitars from the basic concept of the Bigsby vibrato, but with many engineering improvements. The entire vibrato unit is top mounted. The strings feed through six holes in the upright plate at the rear of the unit (somewhat similar to the Fender Floating Trem) and the bridge is also rigidly mounted. But the string saddles are vertically mounted grooved "wheels" that roll with the string during vibrato usage, and also make palm muting very easy to achieve. Moseley advertised the unit as the "feather touch" vibrato, and the touch is exceptionally light with all but heavy gauge strings. Pitch stability is excellent. Moseley made several designs of the unit, the first