Which FileInputFormat to use for fixed length records?

[yz5od2]

Hi,
I have input files, that contain NO carriage returns/line feeds. Each  
record is a fixed length (i.e. 202 bytes).

Which FileInputFormat should I be using? so that each call to my  
Mapper receives one K,V pair, where the KEY is null or something (I  
don't care) and the VALUE is the 202 byte record?

thanks!