Tri – Lock is the modern , patent joint paving constructional type on base „ key and lock", which provides extraordinary conformability, designate elasticity and simple mounting without using mortae and glues. Tri - Lock is against - erosive and system of transport that the it is possible use for fortification erosion heavy - laden surfaces and their resulting grassing, bank reinforcement, streams and rivers, fortification erosive slopes round motorwaies, for construction parks, waies.