D'S T-SLIDE KNOCKEROUTERLocal Springfield, Missouri technician, Duane Lewis, designed and manufactures these handy tools used for removing slightly stuck tuning slides. The seven different sizes are shaped and contoured to cover practically all tuning slides from trumpet and cornet on up to sousaphone. Simple to use place contoured end against inner surface of slide crook and lightly tap with mallet. Made from solid oak with cushioned end to protect against damage to the