M1

= M1 = The M1 is a common key profile which is widely used by Master Lock padlocks and many knock-off brands.

These locks include the Master Lock No 1, 2, 3, 4, 5, and 6. The blank has space for 4 pins stacks and is widely produced by key blank manufacturers such as ILCO and HY-CO.

Master Lock uses the part number 1K for their key blank.
 * ILCO 1092 or M1
 * JMA MAS-1
 * Silca MS2
 * Taylor 92