This well-designed Newton/Metric Spring Scale (2.5N/250g)  can be used to measure the mass of objects in both Newtons and grams.  Turning a nut allows this scale to be adjusted to zero. The scale is also designed not to be fully stretched in order to protect the spring from damage.

Dimension: 
33 x 22 x 250 ~ 320 mm

Warning: Small parts may be a choking hazard for children 3 years old and under. Adult supervision is required.