For example: Agilent E4440A or Anritsu 68369
Attenuator
Weinschel 2-6
Fixed Coaxial Attenuator:18GHz,5W,6dB,1.35dB Output SWR,N Female

Manufacturer: Weinschel
Weinschel 40-20-34
Weinschel 40-20-34 High Power Fixed Coaxial Attenuator:1.5GHz,150W,20dB,1.1dB Output SWR,N Female - N Male

Manufacturer: Weinschel
Vaunix LDA-302P-1N
10 - 3000 MHz Digital Attenuator, 2 Watts, 1.0 dB, N Connectors

Manufacturer: Vaunix
Vaunix LDA-302P-2N
10 - 3000 MHz Digital Attenuator, 2 Watts, 2.0 dB, N Connectors

Manufacturer: Vaunix