1、Safety Warning: These high visibility reflective stickers stand out on the road even at night or in a dark environment, which will effectively make the rear vehicles notice your vehicle to ensure driving safety. 2、Durable Construction: Circular reflectors are made of high quality ABS plastic, scratch‑resistant, fadeproof and waterproof, durable and not easy to break or crack. 3、Application: Perfectly fit for bicycles, semi trucks trailers, bikes, boats, service trucks, buses, service vans, utility trucks, parade floats, horse trailers, utility trailers, pick up trucks, and much more. 4、Easy to Install: Thread size of M6x1.0. You just need to remove the stock reflector and replace the new round reflectors back into place. 5、Package: Comes with 4pcs round reflectors of red color, with high reflective lens cover, not easy to fade and has long service life.