The Brunel Models Ballast Spreader comes in three models for HO - one designed specifically for code 100, one for code 83 track and one for code 70 track. The grooves that fit over the track are exactly the right size for code 100/83/70 rail and minimises any excess ballast being left beside the rails. The Ballast Spreader can be used after the ballast has been laid and glued to clear any ballast particles that have been glued to the sides of the rails, particularly on the inside and helps produce smoother running. A version for N Gauge (Code 80) and O Scale (code 143) Flat Bottom rail is also available .