Technology index following: high hosted capacity, highest can up 32kN or 128kN/m, side from small, minimum can up 5cm, easily adjustment, installation Shi no noise, and no dust, get has official of certification, can for static and dynamic hosted, anti-corrosion performance good, used stainless steel or hot dip plating zinc steel quality; these quality characteristics makes slot type pre buried pieces steel became all designers and user indispensable of a products.