Eliminating bookmark (key/rid) lookups

When we were looking at the index scan and table scan section we were able to eliminate the scan which was replaced with an index seek, but this also introduced a Key Lookup which is something else you may want to eliminate to improve performance. 

A key lookup occurs when data is found in a non-clustered index, but additional data is needed from the clustered index to satisfy the query and therefore a lookup occurs.  If the table does not have a clustered index then a RID Lookupoccurs instead.

http://www.mssqltips.com/sqlservertutorial/258/eliminating-bookmark-keyrid-lookups/