Walmart offers the Stalwart 60-Piece 3.6-volt Cordless Rotary Tool Set for $12.26. Choose in-store pickup to dodge the $5.99 shipping fee. That's the lowest price we could find by $6. The rotary tool runs at 10,000 rpm and features a spindle lock button. It comes with a 60-piece accessory kit that includes sanding, cutting, drilling, and polishing bits.