It's Academic Folding Ruler
https://theclassroomstore.com/products/Its_Academic_Folding_Ruler
Foldable for storage but still accurate for straight lines and measuring.
Price
Qty
07029 - Each
3.25
ea
Each tile is exactly 1 inch. Great for teaching fractions, odds and evens or just to fidget. Standard length of 12" (imperial) and 30 cm (metric).
