3d printer bed level adjustor

I found that it is difficult to adjust bed level by program. So, I made this leveller can adjusts visually. Hope that can help adjusting easier.
You needs :
1. M6x55 bolt and nuts x 3 pcs
2. OD12 x 25 spring x 3 pcs
2. OD20 to 25 washer x 6 pcs
to complete this things.