Code completion in completionvalues1.xml for 17[^sp]:
17dp : <b>Density-independent Pixels</b> - an abstract unit that is based on the physical density of the screen.
17sp : <b>Scale-independent Pixels</b> - this is like the dp unit, but it is also scaled by the user's font size preference.
17pt : <b>Points</b> - 1/72 of an inch based on the physical size of the screen.
17mm : <b>Millimeters</b> - based on the physical size of the screen.
17in : <b>Inches</b> - based on the physical size of the screen.
17px : <b>Pixels</b> - corresponds to actual pixels on the screen. Not recommended.