The OSL series open/short/load are used on the test port of the Site Master Series of handheld instruments to establish a reference for accurate measurement. When used with a Site Master, the open/short and load reflection over a swept frequency range can be automatically averaged to enhance measurement accuracy. OSL series Open/short/load comes in both N (Male) and N (Female) connector configuration and consist open on one end, short on other and Load on the tee section.