A LEGO compatible ruler.  3D Printed based on Lego Part Number 852690 (BB0342) which are expensive and no longer made.  So this is a cheaper alternative. My version also has a hole so you can hang it in your workspace! This tool allows you to measure:        1) Stud lengths up to 19    2) Axle/Rod lengths up to 12    3) Brick height up to 10    4) Technic beam lengths up to 16 This comes 3D printed in PLA with the numbers highlighted in white paint.