This is a Dial Test Indicator (Lever Type) which offers you the following benefits: Drastically enhanced durability, sensitivity and visibility. Glare-free flat crystal face allows easy reading of graduations. O-ring seal on the bezel has the effect of providing smooth rotation and prevents dust and oil from penetrating through to the dial face. The stylus length is on the dial face to reorder a replacement Multi-layer coatings on the crystal.