An adapter for testing printed circuit boards which has a support plate and an advantageous fixation of exchangeable spring-loaded contact elements, also known as spring-loaded probe assemblies, therein for providing electrical contacts to a printed circuit board in predetermined contact locations. The support plate (2) is comprised of several layers (20, 21, 22), and the contact elements (4) are set into bores (3) and are removably held and axially locked into place in the bores (3) between two layers (20, 22) by a bead (51) formed on the contact elements, preferably in a vacuum-tight manner.