Spare blade for 300 mm (12″) hacksaws. Blade length 300 mm, 24 teeth per inch. Cobolt iron dumbbells are significantly more durable than ordinary iron dumbbells and are almost impossible to break. Precision-ground teeth improve blade durability and performance when sawing most hard materials. Suitable for e.g. for aluminium, bronze, copper, brass, hard plastics, cast iron, steel and stainless steel.