These rodent gas masks fits mice and rats of all sizes, and they are versatile for a wide variety of applications. The OC gas masks allow you access to the eyes and head of the rodent while sealing the nose and mouth. The gas masks provides stability of the animal for examinations and surgery, and they can be easily incorporated in existing examination procedures. The waste-line connects to gravity or vacuum filters, and swiveling ports allow for greater flexibility in positions. The are easily adapted for stereotaxic applications.