Features Material: Carbon steel plumbs bobs, nylon thread is easy to identify, wear-resistant and not easy to break. Adjustables: Adjustables resistance, suitable for different weights of plumbs bobs; adjustables distance measurement, suitable for different construction conditions. Magnetic Design: Strong magnets on the side can be easily attached to the iron structure. Just lift the plumbs bobs lightly, and there is an elastic wire reel inside to automatically take up the wire. Hanging holes can be hung on nails or hooks, which is convenient for measuring on concrete, masonry and other walls. It is used when the magnets cannot be used to fix the needle. Used: The fixed pin can be pressed and fixed on a wooden board or plaster board (do not hit hard with a-hammer). Wide range of applications, can be used for housing construction, vertical measurement, etc. Notice: Actual color may be slightly different from the image due to different light effect Please allow 1-3cm deviation due to manual measurement Size: 18*12*2.2(cm) Package List: 1/2pcs Retractable Plumbs Bobs