It is its 4-yard production batch number, indicating that it was produced on 20 12 1 month.

The first digit indicates the mantissa of the year, and "2" indicates 2012;

The second letter indicates the month, which starts with n, and n =1p = 2q = 3r = 4s = 5t = 6u = 7v = 8w = 9x =10y =1z =12.

The last two figures are meaningless.