Fix 12 is a surface mount aluminium profile that houses LED strip- it is extremely low profile and will fit in a thin space. This profile is perfect for highlighting and emphasising architectural detail, as well as providing some general Illumination- although one must be careful with putting in high wattage tape as the shallow profile will cause it to overheat. This strip in particular will go well in cabinetry and joinery where it has limited room to fit.
Keep in mind with thin profile however, that it is best used in contexts in which the lit face of the profile cannot be seen (i.e. on the underside of benches, or perhaps lower to the ground) so you don't see the hotspots of the LED chips on the strip. If you want even light, a deeper profile is required.
The maximum LED strip width that can be installed is 12mm.