Ball Efratom is an electronic test equipment manufacturer best known for creating plug-ins for ultrasonic testing. The plug-ins are compatible with the Tektronix TM500 system, a modular system. Ultrasonic testing enables engineers to gauge the internal structure of a piece of equipment using sound waves. In 1994, Datum Inc. acquired Ball Efratom. Today, Datum Inc. continues to design and manufacture frequency and timing products according to high industry standards. The Ball Efratom brand survives at Datum Inc. and in resale stores, despite the fact that it no longer manufactures products under the Ball name. Purchase used and refurbished Ball Efratom portable rubidium frequency standards at ValueTronics.com.