Gravitas Capital Partners LLC has purchased a Middleborough office building for $6.1 million.

The 58,510-square-foot office asset at 151 Campanelli Drive was sold by New Boston Fund. New Boston purchased the property from developer Campanelli for $9.1 million in 2007.

The single-story office property is fully leased to Eastern Bank, with a lease that runs through 2019. The building, located on seven acres of land, was originally constructed in 1989 as a corporate headquarters for Plymouth Savings Bank. The property initially consisted of 25,300 square feet. Two subsequent additions in May of 1996 and November of 2003 expanded the building to its current size.

Colliers International arranged the sale. The Colliers investment sales team of Lisa Campoli, Gail McDonough, Anthony Hayes and Timothy Mulhall worked on behalf of New Boston Fund to close the deal in October. The team was assisted by Colliers’ suburban market specialist David Goodhue.