Easy perfect centimeter sticks - 1 cm and 3 cm

I kept finding myself doing connect the dot measurements for adding seam allowance or measuring leather strips, and despite my best efforts, a large ruler can slip and ruin a line. So I made these centimeter sticks that won't require dots, they can help you draw a perfect 1cm or 3cm from a straight edge. Just place the stick at a straight edge and draw in the groove, making sure your line draws all the way against the edge the furthest away from where you measure from.
So basically:
1: Place