US Patent 12092141 Screw having stacked screw heads

A screw having stacked screw heads includes a screw shank portion with a thread and a screw head portion rigidly connected to each other. The screw head portion is driven to bring the screw shank portion to rotate. The screw head portion includes a first screw head and a second screw head. The first screw head has a first shaped groove on its top plane to receive an operating torque. A neck portion is connected to a bottom plane of the first screw head and a top plane of the second screw head. The second screw head has a second shaped groove on its top plane. The neck portion or the connection between the neck portion and the first screw head or the second screw head has lower torsional endurance than each of the first screw head and the second screw head.