In the context of the input sentence, determine the relationship between 'Equinix' and 'data center'.
Options: currency, director/manager, product/material produced, headquarters location

-- U.S. data center operator Equinix (NasdaqGS: EQIX - news ) to acquire British peer Telecity Group (LSE: TCY.L - news ) (notified Sept. 24/deadline Oct. 29)
product/material produced