En-Mail, which has taken eight months to come to market, is produced from one piece of paper, but the finished item consists of a personalised letter loose inside a personalised envelope.

Sales director Pat Smith said: The biggest problem was cutting out the envelope flap and the side strips where the letter goes inside, and doing it reel-to-reel.

Although MMI is not aiming En-Mail at large-volume mailers, it is suitable for a 50,000-1m print run.

The product, available in C5 and DL sizes, is printed on MMIs Muller Martini web presses, personalised on Oc continuous laser printers, then completed on its Hunkeler finishing line.

The envelope has a curved flap, unlike the usual square, which is intended to reduce its machine look.

The lightweight nature of the finished product means customers can benefit from postage cost savings by using Royal Mails Mailsort Light specification.