When I use the command: show chassis inventory. I found :
Slot Module Serial
---- -------------- ------------
1 CSS5-SCM-2GE F0 JABxxxxxxx
2 CSS5-IOM-2GE E0 JAB08xxxxxx
3 CSS5-IOM-8FE F0 JAB0xxxxxxx
4 CSS503-SM-INT JAB09xxxxxxx
I do not know what is the CSS503-SM-INT.