Fat gripz is a tool used to build strong, big forearms and muscles. It is also use for improving grip strength. Here are some exercises to improve grip strength. Pull-ups is an exercise that will physically assemble your grip strength and forearms muscle. You can enhance the work on your forearms by means of wrapping a towel around the bar. The towel is not obviously gripped and it makes the bar thicker, this makes your forearms work much harder. Dead lifts logically develop your grip endurance and power. It is the best exercise for developing grip strength. You can do this by holding a heavy weight for extended period of time.