The Sterling Group Foundation Fund announced Oct. 6 that it acquired Slingmax Group — an Aston, PA-based manufacturer and distributor of engineered lifting and rigging products, from private equity firm River Associates.

The transaction closed Sept. 30. Financial terms were not disclosed.

Slingmax Group encompasses Slingmax Rigging Solutions, I&I Sling and Yale Cordage. Its products include synthetic and wire rope slings, high-performance ropes and complementary equipment used for lifting, pulling and securing applications.

The company’s operations span design, manufacturing and distribution, serving markets that include utilities, power generation, infrastructure, aerospace and defense, marine, mining and construction.

“We look forward to working with Slingmax’s strong management team to accelerate growth in this next chapter,” Foundation Fund Partner Lucas Cutler said.

The Foundation Fund focuses on lower middle market companies, drawing on Sterling’s industrial operating experience to support growth. Founded in 1982, Sterling invests in manufacturing, distribution and industrial services businesses and manages approximately $9 billion in assets.

Slingmax said its existing management team will remain in place and day-to-day operations will continue as usual.

The sale follows several years of expansion under Chattanooga, TN-based River Associates. River acquired Yale Cordage in July 2020, establishing the foundation for the platform. Yale Cordage subsequently acquired I&I Sling and Slingmax in March 2023, combining complementary rope, sling and rigging businesses under what became the Slingmax name.

In June 2026, Slingmax acquired Wisconsin Lifting Specialists, expanding its Upper Midwest presence and adding fabrication, inspection and certification capabilities. River said the company also invested in leadership, commercial capabilities, engineering and manufacturing capacity during its ownership.