Kapro Magnetic Lock Combination Square Review 325M

Kapro Magnetic Lock Combination Square
PTR Review
  • Build Quality 9.0
  • Feature Set 9.5
  • Performance 8.5
  • Value 8.5

Kapro's knack for little innovations that make an out-sized difference is evident in this combination square. You'll probably find its magnetic hold more convenient than the traditional lock nut's hold.

Overall Score 8.9 (out of 10)

There was a time that I didn’t know how to use a combination square. As a much wiser tool user, I know now that there are so many practical uses for the tool that both Pros and DIYers alike are at a disadvantage without one. Although you may have seen some Kapro level reviews from us before, the company offers a much deeper line of layout and measurement tools. Among them is the Kapro 325M Magnetic Lock Combination Square under review today. It may have a bell and whistle more than your current combo square, so let’s take a closer look.

Feature SetKapro Magnetic Lock Combination Square

  • Easy to read vial
  • Magnetic lock adjustment
  • Stainless steel blade with permanently etched ruler markings (in. and cm)
  • 5 milled sides for superior accuracy
  • Easy Grip magnet-held stainless steel scribe
  • Heavy-duty cast zinc body
  • Belt holster included


You can never go wrong by checking your table saw’s accuracy, which is easy with the Kapro Magnetic Lock Combination Square. Wouldn’t you know? My blade was slightly out of true with the table. The Kapro would probably be worth its price right there. You can also square the blade to the miter slot with a combination square.

Pro Tip: you should be sure that your table saw is unplugged before making any of these adjustments.

The Kapro 325M innovates away the common locking nut with strong magnets that hold the ruler instead. It means that you don’t have to hold the precise measurement steady as you tighten the nut and, of course, don’t have to loosen it when you’re done. You simply push and pull the ruler through the square head’s magnetic field. The magnets create a strong resistance to movement so you can be confident that the ruler will stay where you set it.

Kapro 325M Magnetic Lock Combination Square

At first, I was worried that this would scratch the ruler. But I didn’t see any scratches during the course of the review. The hash marks are etched, so there’s little danger of them wearing off. Kapro doesn’t indicate whether the magnets are rare-earth or not, but there’s no initial cause for concern.

Kapro 325M Magnetic Lock Combination Square

The level vial assists blade and bit height adjustment. I find registering and transferring measurements from the board to blade/bit or board to board is the most helpful use of the Kapro Magnetic Lock Combination Square. I don’t trust myself to use a tape measure that accurately because it never seems to work out! The magnets hold the sharp scribe in place if you choose to score the work instead of marking it.

Price & Value

Combination squares are not exactly a dime a dozen, but they aren’t that far off. You can pick up many of them, like the Empire e250M, for under $20. However, none of the Kapro 325M Magnetic Lock Combination Square’s competitors (that I know of) have the convenient magnetic feature. You’ll have to determine if that’s worth the premium price of $17.99. Given this novel feature and the quality of the build generally, I’d spring for it.

The Bottom Line

Kapro’s got a knack for putting new twists on designs that don’t often get twisted, and the Kapro Magnetic Lock Combination Square shows that. I would love to see it sold as part of a kit with a center head and protractor, too. But even as a stand-alone tool, it’s right on the money.

Kapro 325M making marks on wood

Kapro 325M Magnetic Lock Combination Square Specifications

  • Item Number: 325M
  • 15cm (6″)
  • 30cm (12″)
  • 40cm (16″)
  • Price: $19.83 

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