To provide ruggedness and versatility in lab or field applications, a line of test adapters features precision-machined, passivated stainless-steel construction for long life, repeated use, and corrosion resistance. All adapters provide epoxy-captivated components and are designed for superior electrical performance with low loss and guaranteed low voltage standing wave ratio (VSWR) to 18 GHz. At 18 GHz, for example, the P2RSA-3703 provides VSWR below 1.20:1 maximum. It exhibits insertion loss to 0.2 dB. The adapter provides impedance of 50 1 Ω. It exhibits delay of 76 ps at 18 GHz. The P2RSA-3703 provides 70 percent velocity of propagation. It is guaranteed to perform to a minimum of 500 mating cycles. The passivated-stainlesssteel adapters house an epoxy-captivated polytetrafluoroethylene (PTFE) insulator.