Alligator Sens It valve stems are an attractive option to give your wheels that finishing touch. The stems are TPMS compatible but can also be installed by themselves without the need to be attached to a TPMS sender for those without TPMS or with indirect TPMS. The stems feature a knurled cap with a button that can be used to depress the schrader valve inside the stem to release excess pressure. The valve includes a screw to attach the stem to a TPMS sender if needed as well as a lever bar to stop the valve from turning while the screw is being torqued.