The 3M™ Secure Click™ Quantitative Fit Test Adapter Kit HF-800-03 consists of a fit test head harness assembly and fit test adapter with port that is installed on a 3M™ Secure Click™ Half Facepiece Reusable Respirator HF-800 Series. The HF-800-03 fit test adapter is installed where the speaking diaphragm is normally assembled. Fit test tubing can then be inserted onto the fit test port. After performing the quantitative fit test, remove all parts of the 3M Secure Click Quantitative Fit Test Adapter Kit HF-800-03 and reassemble the 3M Secure Click Half Facepiece Reusable Respirator HF-800 Series per the User Instructions prior to using in a contaminated environment.