Saboda zaɓin kayan hatimi sune EPDM ko NBR.Za a iya amfani da bawul ɗin ƙofar hatimi mai laushi a matsakaicin zafin jiki na 80 ° C.Yawancin lokaci ana amfani da bututun maganin ruwa don ruwa da ruwan sharar gida.Ana samun bawuloli masu laushi masu laushi a cikin ƙira iri-iri, kamar British Standard, Standard German, American Standard.Matsi mara kyau na bawul ɗin ƙofar mai laushi shine PN10, PN16 ko Class150.