The curved arched file keeps your nails from moving from the file while sharpening, and does not slip easily, so you can smoothly sharpen your nails while watching TV or video. Also recommended for toes. Recommended for those who have weak nails and cannot nail depending on the convenience of housework or work. Sharpen your nails and keep your nails beautiful. The concave surface (surface) is a hard type with a third tier. Sharpenable The convex side (back) is finely etched, making it perfect for finishing after cutting nails. Made of rust-resistant stainless steel. The file is durable and does not wear off, so it can be used for a long time.