SL380F SL380F - Code 55 - Single Slip Finescale with insulfrogSingle slips were often used on double track lines to incorporate a trailing crossover into the access for a siding, goods yard etc. The clever geometry of this range enables the modeller to easily create convenient, complex and aesthetically satisfying track formations using combinations of small, medium and large radius turnouts and crossings. Despite a low visible rail height of just 1. 4mm, all brands of N Gauge model locomotives will run on this