Music rolls for the Welte-Mignon T98 system, which was produced from 1924 onwards, are usually called "Welte green" rolls, as the paper used was usually striking green. On the red or burgundy roll boxes, there is a label on the front with the name Welte-Mignon, the roll number, the title and the name of the pianist. The same label is also on the music roll - since the roll runs from top to bottom, the label is normally readable when the roll is inserted. Some rolls also show the date of manufacture. Some rolls are also only provided with typewriter labels. For hanging in the take-up reel there is a hook or a round eyelet at the beginning of the reel. This reel format corresponds to the 88 standard format in terms of dimensions. The paper is 28.6 cm wide.

The majority of the Welte images were taken with the Welte T100 (red) system. After introduction of the Welte T98 (green) system, the images were recoded and punched to the new format. The result is very good. Nevertheless, many collectors prefer the 'original', i.e. Welte red. Since Welte T98 (green) was only introduced to the market at the end of the Pianola era, it is much less common today than its predecessor Welte T100 (red) - as are the music rolls.