Bi-directional wire fences are a type II highway protection net product, requiring a wire diameter of 5.0mm after plastic treatment, with a mesh size of 75*150mm and posts measuring 48*3.0mm, boasting a lifespan of up to 30 years. With the widespread use of bi-directional guardrails in recent years, besides highway applications, they are also used for municipal fences, enclosing hills and lands. The prices vary greatly, from as low as $30 to as high as $200 per set. People often prioritize price over quality, with wire diameters ranging from 2.0mm to 6.0mm all considered part of bi-directional guardrails. Mesh sizes have also been increased in various ranges, and posts are chosen from 0.6mm thickness, with some customers reporting that the side ears of the posts can fall off during installation. This is understandable since the post thickness is only 0.6mm, even thinner in some cases. Protection can only isolate boundaries. High-quality, affordable products are not merely low-priced; their intrinsic quality is particularly important. For temporary use, materials with a lower thickness can be used to reduce costs significantly, but when considering the lifespan, material selection should be done with caution.