The Starrett 222M Sheet Metal Micrometer reaches over the edge of sheet metal and takes measurements away from the edge toward the center. Also for other gaging jobs where a deep throat micrometer is needed. Rounded anvil on 1" (25mm) size gives a point contact for more accurate gaging; flat anvil is also available. The 1/2" and 13mm micrometers have satin chrome frames; 1" and 25mm micrometer frames have black wrinkle finish. 0-13mm, 0.01mm Grad, Ratchet Stop, Lock Nut finish.