Everybody has faced the problem when a pen splits or fractures at the wrong moment. Or when the timber stick has to be sharpened, interrupting others with an irritating sound. Here are some tips which will help you to find the perfect device:
smoothness is the first quality which has to be ideal. There mustn’t be any scratchy feeling or even a sound;
the darkness can be adjustable, but simultaneously without any additional pressing on it;
no smudges must appear on the paper after accidental hand moves;
no dirt smears after erasing.
In addition to aforementioned, the shape of the body has to be comfortable. Luckily, producers generally keep the customer happy with this feature.