The spring balance actually measures force, but for convenience is calibrated in kg on the basis that when it is used normally [weight force] = m * g where m is the mass in kg and g the acceleration due to gravity. (9.8 m/s^2) So you just need to multiply the scale reading by 9.8
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Convenient Weight Marker When ya give this spring scale a tug, the weight marker will slide to the appropriate weight and stay there until ya move it back to zero. This will help ya out when you’re weighing items that are a little on the heavy side. Load, weigh, unload, check your weights…it’s really simple.
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