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

This is such a great set. Im using this for drawing and there are so many great options.

Great product for my son doing his GCSE. Compass with screw adjustment is so much better that the cheap ones with pencils in. well worth the extra money

I used this in my woodshop to layout circles up to 8 inch radius. This required the extension bar that is included with the kit. It worked well, both on smaller circles and those requiring the extension. This was not an ultra-high precision application though, as I was laying out lines to guide carving. The tools in the kit are of decent quality, especially for the price. I am confident they will hold up over casual use. I don't know about using them for true precision drafting, as the mounting system for the extension and the pencil lead do not seem like they could be counted on the assemble the same way each time to sub-millimeter accuracy. But overall, the kit is fine for general woodworking.

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.