The GTM-06 tourbillon minute repeater differs from other repeater wristwatches in a number of details. There is an acoustic reason for the large case (44mm x 15mm), as this generous volume allows the gongs to develop a full and pure sound.

The lugs, which convey the full outlines of the case to the alligator strap, are not as straightforward as they appear. Using specially developed micro-machining techniques that are invisible from the exterior, the lugs are channelled so that the resonance of the case isn't dampened by their mass. This is the result of extensive research and development, combined with the vast wealth of experience acquired by both Bart and Tim Grönefeld during their years of developing and listening to minute-repeater mechanisms.