John Packer JP231 Rath intermediate trombone outfitIntroducing the John Packer JP231 Rath intermediate trombone outfit The JP231 Bb tenor trombone is characterised by a professional standard of workmanship and an extremely high level of performance that is often compared to more expensive, high end models. Its suitable for intermediate and advancing students that are ready to take their playing tot the next level. This durable instrument is created from high grade 80: 20 brass, with an 8" bell and 0.