【MATERIAL】modern plastic; 【DIMS & SUIT FOR】We will provide 3 sizes and recommended usage ranges for your reference (H x W x D): S:1.18 inch x 1.69 inch x 0.47 inch /30mm x 43mm x12mm ,Suitable for chickens from half a pound to about 5.5 pounds; M:1.42 inch x 2.2 inch x 0.47 inch / 36mm x 56mm x 12mm , suitable for chickens from 2 pound to about 7.5 pound; L: 1.46 inch x 2.48 inch x 0.47 inch / 37mm x 63mm x 12mm , suitable for chickens from 4 pound to 10 pounds or more; 【ANTI-PECK DESIGN】Eye protector to calm offensive cocks and hens, keep chicken from pecking each other in order to improve chicken survival rate, lay more eggs. After wearing can not peck feathers, grow fast, but does not affect the food, drinking water; 【INCREASE CHICKEN REARING DENSITY】Reduce flock exercise, reduce feed consumption, Improve chicken woollen appearance, Increase chicken laying eggs rates, increase chicken rearing density, and the feeding density can be increased to about twice the original; 【EASY TO INSTALL】These pinleless peeper chicken peepers are painless and easy to set up, just fix the chicken, open the glasses with your hand or tweezers so that the pins of the glasses snap into the nostrils of the chicken, and that completes the operation; 【PACKAGE INCLUDE】 Come with 50pcs pinless peepers ,1 assistant plier tool and 1 plush bag (color random)