Your MacBook has two ram slots and the maximum upgrade is 16GB (2x8GB). A1278 (EMC 2351). The 16GB Ram kit is only compatible with a MacBook Pro Mid 2010 that has an identifier of 7.1, the other Mid 2010 MacBook Pro with Identifiers of 6.1 and 6.2 respectively are not upgradeable to 16GB, they max out at 8GB (2x4GB).
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