PTC heater with shell1. Configuration.TypeSpecialtyExcellenceshortcomingOthersAluminium shellAluminium shell, with wire and insulating filmFast heat conduct, large ... , air heating, heating a surfaceCeramic shellCeramic shell, with wire and ceramic insulationLow cost, small bulk, insulating shellNot ... can be used for heating liquid, and it’s no problem when liquid was dried.4) Very high ...