The DHCP_FILTER_ENUM_INFO structure contains information regarding the number of link-layer filter records.

 typedef struct _DHCP_FILTER_ENUM_INFO {
   DWORD NumElements;
   [size_is(NumElements)] LPDHCP_FILTER_RECORD pEnumRecords;
 } DHCP_FILTER_ENUM_INFO,
  *LPDHCP_FILTER_ENUM_INFO;

NumElements: This is of type DWORD, which specifies the number of link-layer filter records contained in the array specified by the pEnumRecords member.

pEnumRecords: This is a pointer to an array of DHCP_FILTER_RECORD (section 2.2.1.2.92) structures that contains link-layer filter records.