Mermaid Medical M-Biopsy Coaxial Introducer Needle, Coaxial Needle for M-Biopsy 18Gx10cm-PRO-MAG, RX Only. Single packed device in a tyvek pouches. 10 single packed devices in a || white carton unit box. || The M-Biopsy coaxial needle is used to obtain one or multiple core samples from soft tissue such as the liver, kidney, prostate, breast, etc. and is to be used in conjunction with an M-Biopsy Biopsy Needle for a Bard Magnum or Pro-Mag Biopsy Instrument.