Stop plugs,Threadless Plugs Based on the water flow directions,any of the cooling and heating systems will have the fitting fun Stop plugs,Threadless Plugs feature:How to use it:1 When installing into molds,please make sure the space is at least 0.1mm wider than cooling circuit plugs.2 If there is no specific setting for the coling circuit plugs:first relesae,then using the air spray to reset. ...