ATC Diversified Electronics 339B-200-Q-2-XProduct Attribute Attribute Value Contact Form DPDT Current Rating 10 A Function On Delay Mounting Type Socket Mount Number of Pins 8 Pin Product Description An economical solid state TDR with octal plug in base, the 339B maintains excellent repeat accuracy despite wide voltage and temperature variations. even after long periods of down time. Two models are available. Each has six dial selected ranges from fractions of a second to as long as 10 hours.