PORT HURON, Mich. — International Service Leadership, a technical and marketing training company for contractors, has been purchased by three mechanical contractors.

David Squires, president of Port Huron, Mich.-based Online-Access Inc.; Bob Wilkins of Wilkins Mechanical Services in Bedford, N.H.; and Milton Baum of Keil Heating and Air Conditioning in Riverdale, N.J., bought the firm.

Officials said the company will retain its independent residential HVAC contractor focus, and will continue to conduct three meetings per year. Headquarters will remain in Nashville, Tenn.