A device for securing threaded rod can include a housing and a threaded rod locking mechanism. The housing can include a rod locking body with a tapered bore, and a housing extension extending from an end of the rod locking body. The threaded rod locking mechanism can include two plunger pieces, each of which are movable within the tapered bore and include a respective threaded inner surface and a respective sloped outer surface that can engage the tapered bore. The threaded rod locking mechanism can also include a spring disposed within the tapered bore to bias the plunger pieces towards a narrow end of the tapered bore. The plunger pieces can be urged towards each other and towards an axis of the tapered bore by contact between the outer surfaces of the plunger pieces and an internal surface of the tapered bore.