Dipec has moved into high value-added applications and counts protective safety screens in the royal seating area at Cardiff's Millennium Stadium and work for the Welsh Bafta awards among some of its work.
The MBO by Mr Callow followed the decision by Dipec's founder and managing director, Paul Robinson, to retire.
Dave Perez, investment executive at Finance Wales, said Dipec was a good example of how an owner-manager should consider the succession of a privately-owned business.
"We advised Dipec on a raft of issues, including introductions to Finance Wales, financial projections and input from lawyers and accountants, and we think Jason is well positioned to take the company to the next level."
Liz Hitchings of SRBlegal said, "With Jason's detailed knowledge of the industry and his commitment to the business, I am confident that Dipec will go from strength to strength under his ownership."