These 2”- 50 mm scales are printed on flat white, grey, or black pressure-sensitive paper with a peel-away backing.
For photos on horizontal surfaces, just lay the scale in the scene.
For vertical surfaces, such as bullet holes or blood spatters on walls, just peel the backing off and press the ruler to the surface.
These scales have non-permanent adhesive and can be easily removed from evidence without damage.
Scales are in quantities of 50, individually cut