Zt-Zero Tolerance 0357BW Assisted Opening Liner Lock Knife Titanium Blackwash Plain Edge. The new zt 0357 is a premium knife designed for cutting for hard use. The textured black G-10 handles allows a secure grip when cutting. The CPM-20CV blade steel is tough with a 59-61Hrc and holds its edge. The 0357bw has the SpeedSafe assisted opening bar for quick opening.