Mid-market investor Riverside Co. invested an undisclosed amount in Boston-based specialty glass manufacturer Woon-Tech.

Woon-Tech, which makes glass products for shower enclosures and other residential and commercial applications, will serve as an add-on to Riverside's Cardinal platform.

Cardinal is a portfolio company of the private equity firm that makes glass products for residential, hospitality and light commercial use. The introduction of the specialty glass manufacturer will complement Cardinal's product offerings and will aid in its geographic expansion.

Jones Day and KPMG served as the legal counsel and accounting adviser on the transaction, respectively, while Antares and John Hancock provided incremental financing for the acquisition.