Coverage/ 18 s.m./lt. undiluted, 5-10 s.m. depending on dilution.
HMK® R771 is a special acid based concentrated cleaner for removing extremely persistent atmospheric de-posits, oily soot, water marks and mineralization from rough granite, gneiss and sandstone facades. For external use only. Instructions: Ensure all adjacent surfaces are protected against spills. Always mix solution where spills can do no damage. Work on manageable areas at a time. Before application wet the surface to be treated and apply the mixture diluted 1:3 to 1:5 depending on the level of contamination, with a scrubbing brush, stiff brush or a suitable pad. Work into the surface and leave for a short time but do not allow to dry. Scrub the area again and remove the dirty liquid. Afterwards clean the area thoroughly using HMK R155 Intensive Cleaner - acid free diluted with clean water (about 1:10) and remove the dirty liquid. Afterwards rinse the area thoroughly with clean water. Repeat the procedure in the case of very strong contamination.
Note: Do not apply in direct sunlight. Acid sensitive surfaces, polished natural and artificial stones, metals, plastics, glass etc. will be damaged by contact with HMK R771.