Mdevices STD Extension Set - MLL to NAS, 15cm, 200pcs / Box (IV052415)m devices Standard Bore Extension set, Single Lumen with Needleless Access Site is 15cm in length. This set has a male luer lock with rotating collar at one end and the Needleless Access Site at the other end. The set should always be primed prior to connecting to a peripheral catheter or access device on an IV administration set.