For all HO and OO tracks. One set includes 2 Tools. This very useful track alignment tool is designed to keep the same distance between the centers of adjacent and parallel tracks. You can adjust the distance between the mids of tracks from 30 mm to 90 mm or from 1.2 inch to 3.5 inches. With Parallel Track Tool you can lay your straight and curved tracks in perfect parallel with ease.
Better than fixed ones
I already have the fixed version but this is much better.