Cantilevers of the 15 series are generally used in tapping mode for imaging hard samples, when the high topographic and phase contrast are necessary. The 15 series is also good for non-contact mode.
Probes with overall conductive chemically inert 30 nm Au coating with 20 nm Cr sublayer on the tip and backside of the cantilever. Resulting tip radius is below 35 nm. The coating may cause cantilever bending within 3°.