TAIANJI Compass with Locking Screw, Stainless Steel, Quick Adjustment Compass, Geometry Drawing Leads for Primary School, Students, Set

100% metal: There is no plastic in its construction, it is made entirely of metal; the lightweight, nickel-plated compass of high quality ensures that you use it for a long time. Easy to use: whether you are an architect, mathematician, engineer, carpenter, student, teacher, artist, it can be easily used with a good adjustment range. Precision compass with spring bow head: the middle wheel has a compass and a spring to prevent accidental movement of the legs. Adjustment dial and lock valve: the compass can be adjusted to prevent accidental leg movement. will not slip out of your hands. Use this compass to draw a perfect circle. Bring your own lead core: you do not need to find another pen, you can use the included lead core directly for doodling and drawing circles. You will find that the compass is not so cumbersome to use.