10° / tacks

10°, this is its name. As you can see, the defect that normal tacks fall off easily from the wall can be solved.

When 10° is pinned on the wall, the slope of a the needle can nailed on the surface, even thought it’s full of used holes. The 10° does not fall off easy like normal tacks.
Therefore, probability of falling off and making danger can be decreased lots.

Easy to pull out or pin the 10° is the main designing concept of its shape. Another concept can not be ignored either the safety. Because the needle head always lies on floor, you will not injured by it anytime.