Amazon has the 6-Piece Amazon Basics Diamond Needle File Set (150 grit teeth) on sale for $6.69 with free shipping on $25+ or with Prime. Includes round, half round, flat, tapered flat, triangular, and square shapes.

Also on sale:

• Standard 6pc Needle File Set for $4.12
• 3pc Amazon Basics Wood Rasp File Set for $8
• 5pc 8" Steel File Set for $10