In 1904, M. Welte & Söhne of Freiburg brought the Welte-Mignon music rolls onto the market as the first reproducing rolls. Welte-Mignon T100 rolls are usually called “Welte red” rolls because the paper used was such a striking red. The paper is 32.8 cm (12⅞ in) wide. There are Welte red rolls in T100 format but also in other paper colors, green and white – depending on the place of manufacture and paper availability. The mostly burgundy hinged roll boxes bear a label on the front with the name Welte-Mignon, the roll number, the title and the pianist. In the early days, also the recording date of the piece. As with all roll types, the perforations for the 80 notes are in the middle area – at the edges there are 10 perforations each for bass and treble expression control.
The same label as on the roll box is also on the music roll – since the roll runs from bottom to top, the label is upside down when the roll is inserted. There is a round eyelet at the start of the roll for hooking it into the take-up spool.