Suited to anyone dealing with thick calluses or rough, dry skin on the feet who wants an at-home tool for maintenance between pedicures.

Not recommended for people with diabetes, poor circulation, neuropathy, or any broken or infected skin on the feet - callus care in those cases is safer left to a podiatrist or medical professional.

Thick calluses on the heels and balls of the feet are often too hardened for a pumice stone to make much of a dent; a nickel file's coarser surface can reduce that buildup more efficiently.

It's a low-cost way to keep calluses in check between professional pedicures rather than letting them build up untreated.

Used dry, with a light hand, and in short sessions rather than one aggressive pass.

• Make sure feet are clean and completely dry before starting - do not use in the shower or right after soaking.
• File calluses and rough areas using gentle back-and-forth strokes, checking progress frequently.
• Use light to moderate pressure only; stop before skin feels raw or overly smooth.
• Rinse feet and apply a foot cream or moisturizer afterward.
• Clean the file with warm water and antibacterial soap after each use, and let it air dry before storing.
• Limit use to about once or twice a week rather than daily to avoid over-filing.

• Pro: Nickel grit is more effective on thick, hardened calluses than a standard pumice stone.
• Pro: A durable, reusable tool rather than a stone that wears down or a disposable pad.
• Pro: Inexpensive way to maintain feet at home between salon pedicures.
• Con: Aggressive or repeated use can remove too much skin and leave feet sore or sensitive.
• Con: Needs to be cleaned and sanitized after each use to avoid harboring bacteria or fungus.
• Con: Not appropriate for people with diabetes, neuropathy, poor circulation, or broken/irritated skin.