Track layer PKP 25/20.1i is a special bridge crane designed for laying and removing of 25 m long (and shorter) railway tracks on wooden or concrete sleepers and of maximum weight of 20 tons.  Track layer can be used during building of bridge constructions, mainly for laying of IP girders. All active track layer parts are driven by means of hydraulic pump connected to PTO of the towing truck. Control voltage of 24V DC from towing truck battery. TATRA T 815, event. T 148 can work as a towing vehicle, converted for ride on rails, and may be used for towing of braked as well as unbraked load. Device is designed for work on straight rails or in railway bend, with track gauge of 1435 or 1524 mm; it is equipped with rotating beam, which enables work of PKP layer even in small railway bends (also 150 m), with the length of track part of 25 m. This innovated PKP version considerably improves work hygiene and safety, mainly as concerns noise level. Electroproporcional controlling enables better response of trolleys movement.