Bi-metal jigsaw blades for metal, in 75, 105 and 155 mm. The fine 1 to 1.2 mm tooth pitch is what makes them work: metal needs several teeth engaged at once, and a coarse blade will snatch and snap. Bi-metal construction pairs a hard cutting edge with a flexible back, so the blade survives the flex a jigsaw puts into it instead of shearing. Run them slower than you would in wood and let the blade cut rather than pushing it.
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