Smarts uses information in the entPhysicalTable (1.3.6.1.2.1.47.1.1.1.1) to discover cards as in the following:
cardTypeOID { ".1.3.6.1.2.1.47.1.1.1.1.3" }
cardDescrOID { ".1.3.6.1.2.1.47.1.1.1.1.2" }
cardSerialOID { ".1.3.6.1.2.1.47.1.1.1.1.11" }
This can be seen in the ic-cisco-loadbalancer-ace.asl file found here:
<BASEDIR>/rules/discovery/ic-cisco-loadbalancer-ace.asl