Welch Allyn disposable polypropylene ear specula in 2.5mm and 4.0mm sizes are convenient, safe, and economical. Complete instrument includes insufflator fitting and tube of 5 each 2.5mm and 4.0mm specula. Ophthalmoscope features 2.5v halogen light source for true tissue color and long lasting lamp performance; 5 aperture selections (small aperture, large aperture, fixation aperture, semicircle aperture, and red-free filter); 17 lenses from -20 to +20 diopters for better resolution; illuminated dial; silicon coated protection of glass components. Built-in lens dust cover. Rubber brow rest prevents scratching of eyeglasses. Pocket clip with integral on/off slide switch for ambidextrous use. Otoscope and opthalmoscope head made from polymid - an impact resistant space age thermoplastic. AA metal battery handle interchanges between pocket otoscope and ophthalmoscope. Lifetime Quality Performance Guarantee on optics.