The gravel bag is filled with gravel/little stones and put on the silage covers to stop the covers blowing away in the wind.
Silage Bags Details: 1. High strength and tensile strench, elongation, anti-puncture and tear resistance. 2. Made of virgin polythene the same with Secure Covers 3. Easy to install, economic and secure solution 4. Treated with UV: Ensure the nets keep long lifespan