@jacqueslees: Type 300 Fastening System for Shouldered Ballastless Track The Type 300 is a fastening system for ballastless track. It is a non-separated (direct) fastening for sleepers / track slabs with concrete shoulders. It is available in two variants: Type 300-1a and Type 300-1U. Its main structural features are as follows: 1. The spring clips are fastened by means of sleeper bolts engaging pre-embedded sleeves in the sleeper / track slab. 2. Gauge plates are installed between the rail and the concrete shoulder; lateral (left/right) adjustment of the rail is achieved by replacing the gauge plates. 3. Rail height adjustment is achieved by inserting height adjustment shims.