The M-451-881-91KW402-R from Narda-MITEQ is a 90 Degree Hybrid Coupler with Frequency 450 to 880 MHz, Average Power 1000 W, Insertion Loss 0.2 dB, Isolation 20 dB, Amplitude Balance ± 0.75 dB. Tags: Drop In. More details for M-451-881-91KW402-R can be seen below.