Abstract: A fluid transfer nozzle for fuel oil and other fluid products allows for the one step removal of locking caps for vertical filling pipes. The locking cap includes a detent mechanism that, under the force of gravity, engages an obstruction within an input port of the pipe, preventing its rotation and therefore its removal. The nozzle has a socket within its mouth that engages the cap to allow rotation of the cap with rotation of the nozzle. Also within the nozzle mouth is a magnetic element that generates a magnetic field to draw the detent mechanism into an unlocked position against the force of gravity. With the cap so unlocked, the nozzle may be rotated to loosen the cap and allow its removal.