Mr. Pen- Professional Compass with Lock, Up to 18 inch Diameter, Compass for Geometry, Drafting Compass, Precision Compass Math, Compass Drawing, Compass with Wheel, Metal Compass Geometry

Update: I contacted the seller and his response was super fast and sorted out the problem right away. We now have a compass that works well and that one must have been a one off one that has a problem. My son loves it and the feature where you push both bottoms to expand it quickly is super useful when he is doing his geometry homework. That way, he doesn’t have waste time using the small dial to expand the leg or reduce the size. ————- (Old review) I was excited to get this for my son for his Geometry class. So was he. All are great such as refills, extra screws, the little metal plate as a screw driver to tighten the screw for the leg that bends, additional leg to draw a big circle (although this isn't necessary for his class), but one slight oversight which is annoying to use is the screw that tightens the legs from bending. The screw head is so shallow, I cannot tighten it before threading the screw. Needless to say that I cannot tighten it. So, when my son uses it, it kept bending when he's putting his point down on the paper firmly so that the compass won't slip off. I told him to grab the bottom part of the leg while he is pushing down on it. Contemplating on returning it and see if we can get the proper one to tighten the legs. But the inconvenience of it... sigh... If they could just replace the screw (if that screw can be replaced), that would be perfect. All other features function fine and would have been a great compass with 5 stars.

Muy bueno, estudio arquitectura y me ha funcionado para todo

あちこち曲がってたり、作りが雑で使いもんになんねー

Problem with many compasses is that the radius can vary during use, with the slightest bump, or uneven pressure when drawing. The Mr Pen compass is sturdy, has a sharp point and almost every movable piece can be easily secured by tightening the various screws. The only bits I couldn’t tighten, I immobilised with a little cellophane tape or electrical tape. I can now draw at least 20 circles with the same radius, without checking and readjusting the radius for each circular arc. If you’ve ever has trouble using the expensive brand-name compasses, you might be pleasantly surprised how the Mr Pen compass is *much* more reliable. I heartily recommend this compass. The only downside is the international freight cost which more than doubled the price - even with Amazon Prime - the cost is disguised in the cost of the compass, and not separately itemised. In the US, you’ll get one 1/3 of the price I paid.

Bien