An extremely effective glass foot, toe nail, and nail file. The double sided etched suface is graduated from smooth to rough.The file is gentle to use and the etched surface is highly durable. The Prolyne glass foot dresser is very effective in thinning thickened nails, reducing callous and hard skin on the ball of the foot and smoothing dry cracked heels. Regular use can reduce the incidence of heel fissures and relieve ball of foot pain. A moisturiser such as Flexitol Heel Balm should be used daily after filing.The file is very hygienic and can be sterilised if necessary.