It has been configured with directional feeders and managing director Richard Haines said the machine would improve turnaround times on medium- and long-run mailings.
The line is the third installed at Mainstream's facility and follows on just six months after the last investment.
Haines added: "We were blown away with the response to the line. Within the first month, we had processed an additional 3m packs and we are able to continue building on this offering."
Mainstream Direct has a turnover of £3m and employs 60 staff. It specialises in data, lasering, hand fulfilment and polywrapping.
