This large Superslick bell cover is made from a high quality double-brushed cotton cloth weave that will not scratch instrument surfaces. This large size cover fits up to a 17" bell and is perfect for the French horn. The covers tie easily with the nylon drawstring cord. These covers will not impact the intonation of the instrument and have minimal-to-no resistance when playing. The non-stretchy material ensures even coverage surrounding the bell and can secure tightly around most bell sizes. To clean, hand-wash only. Superslick does not guarantee efficacy against stopping the distribution of respiratory aerosols that are released while playing wind and brass instruments.