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/
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