They are hardly suitable for aluminium. Definitely not for steel. For hard materials it is better to buy a proper tap. 3 stars because they are cheap.
Impact screwdriver Makita TD0101F, 230 W
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𧱠Bosch 2607017164 Piece Setter Masonry: Advanced Tools for Precision Masonry Work
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Tool set Ombra OMT94S12, 94 pcs, brown
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Tool set Stels Tool set, 1/2", 1/4", CrV, plastic case 94 pcs, Stels, 94 pcs, black
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Enhanced Cutting Efficiency with Olson FB23370DB 0 025 2 Inch Blade
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POWERTEC 62-Inch 8-Inch Blade - Model 13132X
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πͺ Bi-Metal Cutting Blades: Imachinist S933414 - Enhancing Precision and Performance
Olson 80 Inch Blade FB14580DB-025