This is a multi-pack of Mutec Mutes. It includes models: MHT107 Straight mute, MHT145 cup mute and MHT164 warmup mute. All aluminum. MUTEC Mutes offers a comprehensive line of Trumpet mutes for a range of playing styles. All the brass instrument mutes are professionally designed and tuned to be free blowing and provide excellent intonation in all registers.