Price history on Walmart.com for
Jo-Ral TRB-4B Brass Bottom Bass Trombone Straight Mute
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The Jo-Ral 4B Bass Trombone Mute was designed for an exciting tonal quality that results in near-perfect intonation. They are made of spun aluminum and have been tested to perform evenly in all registers. Many models are also available with brass bottoms-offering a slightly warmer moderately dark sound or with copper bottoms which produce an even warmer darker rich sound.
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