SAE 5-hole mount, C-Ring Flange for Mounting SSS/SSL Tank Liquid Level Sensors. The SSS and SSL models which have a common SAE 5-hole pattern and typically mount with a gasket and screws. The model S3 and S3U which have a 1.25” BSP-threaded mount. And the S5 and S5U which have a 1.5” NPT threaded mount. The FLS-U adapter in this entry will allow you to mount a Wema Flanged (SSS or SSL) Tank Sensor to your water or fuel tanks. The stainless steel FLS-U Under Ring Adapter (installs inside the top of the tank) has threaded fastener holes in an SAE 5-hole pattern. Can be used on plastic, metal, and fiberglass tanks. The FLS-U Under Ring Adapter can also be used in conjunction with an FL-2WE Top Adapter to mount S3U BSP-threaded tank sensors in a tank hole with an existing 5-hole pattern. To Install a new Threaded Sensor installation, you will also need the FLS-U Under Adapter, which will provide the necessary threaded fastener holes. • To retrofit a replacement Threaded Tank Sensor, you will need the FL-2WE Top Adapter, which will match up with the existing threaded holes in your tank. To Install a Flanged Sensor: • To retrofit an SSS or SSL flanged tank sensor (which come with a gasket), you will not need an adapter, as your tank will already have the required threaded mounting holes. • For a new flanged sensor installation, you will need to use the FLS-U Under Adapter to provide the necessary threaded mounting holes. When mounting a sensor in tanks with a thin top KUS recommends using an FL-2 Flange Adapter together with an FLS-U Under-Ring Adapter to secure against leaks.The hole pattern on the FLS-U fits the 5 inner holes on the FL-2.