Abstract: To eliminate the excessive time and labor involved in the installation and removal of multi-contact module bars of receiver frames and/or individual test adapter frames, a self-contained module bar is equipped at opposite ends with beveled spring-urged plungers which can snap into receptor recesses provided in a receiver inner frame or in a test adapter frame. The plungers are retracted by use of a simple tool to allow quick removal of the module bar. A spring clip on each end of the module bar assures firm contact of the module bar with datum surfaces of the receiver frame or individual test adapter frame.