The tester has a sensing tip (6) of standard roundness and a handle (1) for manipulating and guiding the sensing tip over a surface (7) under test. A spring element (2) arranged between the handle and the sensing tip is elastic in at least one spatial direction and remains stable in at least one other spatial direction to guide the tip over the surface. The spring element can be a flat spring. The handle has recesses (8-10) for sensing the surface roughness. The recesses have separation, depth and size matching at least three fingers of a normal right or left hand. The test tip and spring are retractable into the handle.
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