Pinkeye is most often a late-summer problem, generally caused by bacteria from flies or insects entering the eye of calf or adult. The bacteria melt the surface of the eye causing an ulcer to develop. Early identification and treatment is the key to control of this painful disease. After treatment with antibiotic or other topical remedy (consult your veterinarian), the pinkeye patch can be applied to protect the eye and aid recovery. The patch will fall off naturally in about 10 days. Our patches are Shut-Eye brand from USA. The Shut-Eye size allows some natural movement of the eyelid. Each pack of 10 patches includes glue and instructions for use.