Large lego-like concrete blocks can be used to temporarily regulate traffic, reroute traffic, or secure roadwork sites. Reflectors are often added to make the collision protection blocks visible in the evening and at night. This makes the blocks especially useful for roadblocks and collision protection in hangars, buildings or structures. They can also be found in ballasted site fencing systems, and are suitable for securing tents used as temporary workshops. Concrete fencing is characterized by its quick and easy installation as well as its weight. They are also useful as retaining walls for railroad embankments and highways to compensate for changes in terrain. Various retaining wall applications can also be found on the retaining walls page. The flexible mold system is the most cost-effective method of providing the flexibility to produce concrete blocks in a variety of sizes and shapes. The products are easy to use and require little investment.