Greenhoe Ralph Sauer, the brace,

　　threaded trombone slide brace.  circa approx 2005.  This lightly used brace is in great shape and comes with original packaging and infosheet.  It is designed to attach to the bottom of a trombone slide just above the bow.  It uses opposing threading to lightly tension into place on your horn without solder or anything!  It can also be soldered into place if desired.  It is designed to add stability and weight to the sound.