ZF / CHERRY PRODUCTION SCHEDULE
The serial number can be found on the bottom of keyboard.  The last three (3) digits of the serial number are a letter and 
two numbers.  The letter indicates the year the keyboard was manufactured; the two numbers indicate the week. 
A - 1988 F - 1993 K - 1998 P - 2003 U - 2008
B - 1989 G - 1994 L - 1999 Q - 2004 V - 2009
C - 1990 H - 1995 M - 2000 R - 2005 W - 2010
D - 1991 I - 1996 N - 2001 S - 2006
E - 1992 J - 1997 O - 2002 T - 2007
2010 Date Code Calendar
JANUARY FEBRUARY MARCH APRIL
S M T W T F S S M T W T F S S M T W T F S S M T W T F S
1   1 2 6 1 2 3 4 5 6 10 1 2 3 4 5 6 14 1 2 3
2 3 4 5 6 7 8 9   7 7 8 9 10 11 12 13 11 7 8 9 10 11 12 13 15 4 5 6 7 8 9 10
3 10 11 12 13 14 15 16 8 14 15 16 17 18 19 20 12 14 15 16 17 18 19 20 16 11 12 13 14 15 16 17
4 17 18 19 20 21 22 23 9 21 22 23 24 25 26 27 13 21 22 23 24 25 26 27 17 18 19 20 21 22 23 24
5 24 25 26 27 28 29 30 10 28 14 28 29 30 31 18 25 26 27 28 29 30
6 31
MAY JUNE JULY AUGUST
S M T W T F S S M T W T F S S M T W T F S S M T W T F S
18 1 23 1 2 3 4 5 27 1 2 3 32 1 2 3 4 5 6 7
19 2 3 4 5 6 7 8 24 6 7 8 9 10 11 12 28 4 5 6 7 8 9 10 33 8 9 10 11 12 13 14
20 9 10 11 12 13 14 15 25 13 14 15 16 17 18 19 29 11 12 13 14 15 16 17 34 15 16 17 18 19 20 21
21 16 17 18 19 20 21 22 26 20 21 22 23 24 25 26 30 18 19 20 21 22 23 24 35 22 23 24 25 26 27 28
22 23 24 25 26 27 28 29 27 27 28 29 30 31 25 26 27 28 29 30 31 36 29 30 31
23 30 31
SEPTEMBER OCTOBER NOVEMBER DECEMBER
S M T W T F S S M T W T F S S M T W T F S S M T W T F S
36 1 2 3 4 40   1 2 45 1 2 3 4 5 6 49 1 2 3 4
37 5 6 7 8 9 10 11 41 3 4 5 6 7 8 9 46 7 8 9 10 11 12 13 50 5 6 7 8 9 10 11
38 12 13 14 15 16 17 18 42 10 11 12 13 14 15 16 47 14 15 16 17 18 19 20 51 12 13 14 15 16 17 18
39 19 20 21 22 23 24 25 43 17 18 19 20 21 22 23 48 21 22 23 24 25 26 27 52 19 20 21 22 23 24 25
40 26 27 28 29 30 44 24 25 26 27 28 29 30 49 28 29 30 1 26 27 28 29 30 31
45 31
Numbers in green follow the production week code above
Keyboards have a 3-year manufacturer warranty (if issued beyond T20) from date of production year, then week, with a few weeks allowance for shipping.
Keyboards have a 2-year manufacturer warranty (if issued prior to T19) from date of production year, then week, with a few weeks allowance for shipping
Proof of purchase can also be provided for warranty claim