This Japanese multi-purpose hacksaw, from the world renown Piranha Tool Co. Ltd., comes with extremely fine yet sharp teeth (much like its namesake), and very narrow blade, ensuring accurate, clean results. Designed from the ground up to be a multipurpose saw, this saw is great for cutting through cardboard, wood, bamboo, resin, plastic, even nails and metals.This saw has serrations on both edges of the blade, so once it gets dull, you can remove the blade, flip it over and replace it into the handle, giving you a fresh set of teeth and double the life of similar saws.To use this PS-1 Piranha 2 Japanese Fine Tooth Multipurpose Saw Hacksaw, simply grip the handle with your strong hand and run the blade back and forth over the area you wish to cut.To remove the blade of the Piranha saw, grip the handle with your weak hand, and, using a hammer, tap the rear of the blade forward exposing the front part of the blade from the handle's friction grip. Continue tapping the blade out until a sufficient amount of the blade is exposed (a little under half) then turn the saw with the teeth side facing up and strike the newly exposed top of the blade against a hard and durable surface until the blade pivots out from the handle's friction grip, then simply work loose to remove.To replace the blade simply side the rear of the blade in from the side (not the top) of the friction grip, then, holding the handle with the front of the blade on your work surface, repeatedly tap the rear of the handle with a hammer, working the blade backwards into the friction grip. Should the blade start to pivot upwards, position the saw with the teeth of the blade on your work surface and tap the top of the friction grip with a hammer until the blade is fully seated, then resume working the blade backwards. Continue until the blade has been fully set in the handle with the friction grip extending a centimetre or so beyond the blade, once this is done crimp the friction grip with pliers or similar tool to ensure the blade will not work loose while sawing.Be sure to exercise caution when replacing the blade, as mishandling of the blade may cause injury. Cut proof gloves and garments are recommended.Approximate dimensions:• Blade: 165mm in length• Grip handle: 120mm in length• Overall length: 29cm