I like the Kensington trailer screens. They have buckles with metal grommets to attach to my trailers. The screens are made of a heavy mesh that helps to keep bugs, rocks, and yes even birds out of my trailer when parked and when driving down the free way. I deliberately get them larger then the window to protect my horses. Yes, a fly mask will help, but these keep things from flying into my windows. Thankyou Kensington. Great product.