PMI Model No. LM-618-10-1W-SHS-1-M is a high speed, high power limiter that operates from 6.0 to 18.0 GHz.  This limiter handles 100 W peak power with a pulse width of 1 usec. The insertion loss is only 1.5 dB typically and has a VSWR of 2.0:1 maximum. 

This limiter is supplied in a small housing measuring only 0.5" x 0.5" x 0.22".

http://www.pmi-rf.com/products/limiters/LM-618-10-1W-SHS-1-M.htm