A device that can be used to insert a probe into a filtering facepiece for fit testing. The device preferably includes a holder for the probe; a handle to apply force directly or indirectly to the probe; magnets that assist with alignment of the holder and the handle during a process of inserting the probe into the filtering facepiece; and a spring that facilitates separation of the holder and the handle after insertion of the probe into the filtering facepiece. The holder may further include a puncturing device to facilitate insertion of the probe. The holder and the handle preferably are separate elements positioned opposite each other to apply force to the probe. In some aspects, the holder includes a piston for driving the probe into the filtering facepiece. The spring may surround the piston. The handle preferably includes a recess capable of holding a fastener for the probe. The magnet(s) may be of any shape and type, but preferably are torus shaped neodymium magnets. Also, associated techniques.