steel Construction plumb bob-- suitable for furniture decoration, building foundation level measurement, vertical detection, Retractable line reel-- plumb for surveyors, excavation contractors, and foundation contractors Hanging wire hammer-- steel plumb the hammer body has high concentricity, and the same inclination angle on both sides makes the plumb not eccentric in actual use, which better improves the measurement accuracy Building plumb-- falling line, also known as plumb, is mainly to measure the verticality of objects, and is more common in construction engineering Plumb with string-- the descending line, also known as the plumb line, is mainly to measure the verticality of objects, and is more common in construction engineering