So you want to build a stronger core? A decent ab wheel roller can help. The Fit4U Multi Action Ab Wheel Roller is decent for exercising your core, abs, back, and shoulders. When you want to change the intensity of your routines, switch from Center to Offset mode. These wheels are larger in diameter than a few other ones we have seen. You do get exercise tips to get started. What do you think? What’s your favorite ab wheel roller?