The Krpan 4SI winch is defined by robust, proven construction, carefully selected materials and high operational safety, with every unit undergoing 100% effective final inspection before delivery. Pulling force is 40 kN, or 4 tonnes, enough for hauling medium-sized logs in demanding terrain. Braking force is 50 kN, ensuring safe operation and load control when descending a slope. The winch ships with a 70 m steel cable, 9 mm in diameter, long enough for working at a greater distance from the tractor. Operation requires a tractor of 22 to 33 kW, or 30 to 45 HP, making this model accessible for a wide range of smaller and mid-size farm and forestry tractors. Winch dimensions are: width 1,310 mm, depth 450 mm, height with protective mesh 2,100 mm, and without protective mesh 1,320 mm — the protective mesh is an important safety feature that shields the operator in case the cable snaps under load. Weight without steel cable is 240 kg. The winch mounts to the tractor in hitch category Cat 1, standard for smaller and mid-size tractors. Thanks to a balanced ratio of pulling force, weight and required tractor power, the Krpan 4SI is a reliable and accessible choice for private forest owners and smaller farms that occasionally handle log hauling, while its robust build and high safety standards ensure a long working life and safe operation even in more demanding terrain. Compared to the lighter Classic version of the same pulling force, the SI model offers a longer cable and larger dimensions, while compared to the stronger 5 SI and 7.5E models it stands out with lower required tractor power and lower weight, positioning it as the entry model in the SI line.