This is a Mitutoyo Hardmatic HH-331 Dial Durometer, designed for fast and accurate hardness testing of soft materials. It is an Analog Durometer, featuring a Shore A scale and a long-leg type body, which allows for hardness measurement in grooves or holes as well as on exposed surfaces. The dial instrument is equipped with a peak retaining hand to minimize reading errors. It is suitable for testing materials such as natural rubber, soft elastomers, neoprene, plastics, PVC, leather, and more. Power Source: Mechanical/Analog (The corresponding digital models use an SR44 battery, but this analog dial model is primarily mechanical, with some sources mentioning an SR44 battery likely for digital versions or a peak retention function on some variants, but the primary function is mechanical/analo.
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