What is the ruling on using a sandal as a sutrah?

There is no harm in using clothing as a sutrah (barrier), unless it contains a clear impurity or harm, in which case it should not be used as a sutrah. This is because the Prophet, peace and blessings be upon him, forbade spitting in front of one's face. However, if it does not contain any apparent harm or impurity, then there is no objection to it.