Manually operated system. Catheter can be placed by continuously actuating (repeatedly compressing) the driver’s trigger assembly while gently guiding the needle assembly into position. Repeated, full-trigger actuation creates rotational spin of the needle assembly which, when combined with gentle downward pressure, results in controlled IO placement. Once needle assembly is properly positioned, the stylet is removed to expose standard Luer-lock for extension set connection. Once the extension set is connected, aspiration verification, flushing, and selected treatment(s) can be performed.