Check the listing for details. Flanger FA-10P Extend-O-Grip Finger Exerciser Black. Condition: Used, Made in China. Listed at 6.74 USD. The Flanger FA-10P Extend-O-Grip Finger Exerciser in black is a product designed to help musicians and guitarists improve their finger strength and flexibility. Made by the brand Flanger and originating from China, this finger exerciser is a versatile tool for enhancing technique and promoting better overall musicianship. Whether used for daily practice routines or specific exercises, the Flanger FA-10P is a reliable accessory for anyone looking to improve their finger skills and control on their instrument.