The first time I used the spot lock it didn't do what I though it should.....what I had done was push the anchor symbol when the boat was moving about 3 miles per hour...the spot lock reversed the trolling motor and headed back along the path I was on but it didn't stop per the sonar where I had wanted....I did the whole thing over but this time I slowed the boat to creep and depressed the ancho symbol when the sonar was over the spot .....spot lock held this position to within 2 feet in a wind etc per my first post.