Combination Square
An adjustable square with sliding head for marking 45 and 90 degrees, and measuring depth and center.
What is it?
The combination square has a ruler blade that slides in a head with 45- and 90-degree faces. It checks square, measures depth, marks angles, and scribes, making it a one-tool layout station.
What is it used for?
- Marking 45 and 90 degree lines
- Checking square and level
- Measuring depth and center lines
How to choose
Choose a 12-inch combination square with a machined head and a level bubble for layout and verification. A quality blade stays true.
Anatomy
Understanding the parts of a combination square helps you use, maintain, and buy it with confidence.
- Body: the main working portion of the tool
- Working end: the part that contacts the material
- Handle: the part you grip for control and leverage
Materials & construction
Quality combination squares are made from hardened, heat-treated steel (often chrome-vanadium or high-carbon) chosen for strength, edge retention, and resistance to wear and corrosion.
Safety & maintenance
- Inspect the tool before use and replace any that are worn or damaged
- Use the right tool for the job and apply controlled force
- Store tools clean and dry to prevent corrosion
- Wear appropriate eye protection for the work
Also known as
adjustable square, layout square