The Madison Perforating Bone Biopsy Kit with Drill consists of two trays. A hard bone introducer and a drill is on the first tray and a biopsy needle and an ejector pin on the second. The introducer has a trocar tip stylet and a sharp tip cannula which is placed through the soft tissue until it reaches the bone. The stylet may be replaced with the drill if the cortex is dense (except for the minikit). The Madison comes in 11 gauge and four lengths (6.5cm, 8.5cm, 10cm and 15cm). It’s also available in a minikit with a 13 gauge and 6cm long introducer with a removable handle.