The utility model discloses a stop screw, belongs to the technical field of fasteners, and solves the problems that in order to ensure the mounting efficiency and the firmness of the stop screw, constructors often adopt an electric
drill gun to complete the fixing action of loosening and setting, but the situation that the electric
drill gun and a
screw head of the stop screw are likely to be slipped in the process, so that the safety of the constructors is influenced. And when the anti-loosening screw needs to be unscrewed, the anti-loosening screw possibly gets stuck and is difficult to leave. Comprising a lower
screw head, a stud fixedly connected with the lower
screw head and an upper screw head detachably connected with the lower screw head, and a lower cross groove and an upper cross groove are formed in the lower screw head and the upper screw head respectively. When connected with a wood structure, the double-screw bolt can be in threaded connection with a wood block and the like, the lower screw head abuts against the end face and rotates to enable the
insertion block spikes to be inserted into the wood block, and the meshing effect is enhanced. A constructor manually sleeves the protective sleeve, and the plug pin is inserted into the wood block to prevent separation. If an electric
drill gun scratches a cross groove of the upper screw head to cause screw slipping, a screwdriver can be inserted to turn over and take down the upper screw head to facilitate screw withdrawing.