Fig. 7
From: Evaluation of surface roughness of the bracket slot floor—a 3D perspective study
![Fig. 7](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40510-016-0116-2/MediaObjects/40510_2016_116_Fig7_HTML.gif)
Showing images of the bracket slot. a–c The profile lines indicate average roughness (Ra) which is two-dimensional. d The marked rectangular area as a whole indicates the average surface roughness (Sa) which is three-dimensional