This tool should be used as a guide only. Solvalitt may not be an exact match for Sigmatherm 540 by but we have given the closest match we can. Solvalitt should do the same job and have similar properties but you should always read the technical data sheets for both Solvalitt and Sigmatherm 540 to be sure. Please see any notes to see any major differences and call us on 01285 862132 if you have any specific questions.