A set of 4 rust-resistant aluminum trench guards suitable for round and rectangular holes 50-100mm. The dense aluminum wire can effectively prevent leaves, stones, soil, branches, etc. from falling.Block the pipe and the falling pipe. Extend the life of the pipeline. No need to clean the pipeline multiple times, saving time and effort. It can protect the breach of sewer pipelines, waterfall pipes, drainage pipes, etc.leaves, roof moss, branches and dirt. It can also prevent rodents from entering the sewer. The size and shape are adjustable. Very flexible, suitable for different sizes from 2 to 4 inches (rectangular and round flowers).The adjustable drainage hood is best for your drainage pipe. High quality materials. Made of aluminum alloy, not rust, sturdy, corrosion resistance, wear resistance, long service life, can be reused.