Code 11

Code 11 is a numeric, high-density code with one special character '-' . Each character is encoded with five elements, either two wide and three narrow, or one wide and four narrow. The wide elements are a binary one, and the narrow elements are a binary zero.
Code 11 uses two check digits, C and K. The first check digit C is the modulo 11 sum of the weithted products with the weights changing from one to ten. The second check digit K is also the modulo 11 sum of the weighted products with the weights changing from one to nine. The character '-' is assigned the value of ten.
As a rule of thumb, when the message length is ten digits or less, usually only the C check digit is used.

Linear barcode activex control supports code 11 bar code.