Butler Carbon Fiber Leadpipe 547LC for Shires Large Bore Tenor Trombone This is a leadpipe for trombones made by Butler, who produces carbon fiber trombones. Made of carbon fiber, it is extremely lightweight and responsive. Of the two types, S (short) and L (long), this is the L (long) with C (Coarse threads: for Shires) threads. Because it is the long type, you can feel the characteristics of carbon more, achieving a tone like sterling silver while also allowing for a light playing feel like yellow brass. Carbon fiber leadpipes are made tightly and are more prone to cracking than metal, so please handle them with care. Only used for play testing. Please check the photos for details. Thank you.