3M Co., the maker of Scotch tape and Thinsulate fabrics, has agreed to buy the manufacturer Cuno Inc. for nearly $1.3 billion in a move that broadens its line of filtration equipment.

3M also will assume about $60 million in net debt in the deal for Cuno of Meridien, Conn., and says it plans to fund the acquisition with existing cash.

Under the deal, Cuno has agreed to be acquired for $72 per share in cash, a 31 percent premium to its closing price of $54.82 at the time of the deal. Cuno shares surged $14.80, or 27 percent, to $69.62 during pre-market activity.

Cuno products include proprietary depth filters and semi-permeable membrane filters used in a broad range of potable water, health care and fluid processing applications. These products effectively remove contaminants that range in size from molecules to sand particles. Cuno estimates its aftermarket replacement sales at more than 70 percent, which provides a predictable revenue stream. Sales at Cuno have been growing at a compound annual rate of more than 9 percent. For the year ended last October, the company earned $1.92 per share on $351.6 million in sales.

3M claims its current air filtration business “totals well over $1 billion,” and views Cuno's liquid filtration business as complementary.

The deal is expected to close in the third quarter, pending approval from regulators and Cuno shareholders.