The FLS-HT level screw simplifies leveling when installing and adjusting windows and doors. Can be used in wood, masonry and concrete. Replaces wedges and blocks, which provides more space for insulation and thus reduces the risk of cold bridges. Adjustment range is 5-35 mm. The screw has distance marking on the stem for 10/15/20 mm. When mounting or adjusting key, use mounting sleeve or torx bit when window or door is in place.