The TT4-1A-KK81+ from Mini Circuits is a Balun with Frequency 0.1 to 300 MHz, Insertion Loss 0.26 to 2.21 dB, Current 30 mA, Power 0.25 W, Return Loss 1.09 to 30.12 dB. Tags: Surface Mount, Unbalanced to Balanced. More details for TT4-1A-KK81+ can be seen below.