People of different age groups face different handwriting posture problems, so we designed 5 different shaped pen grippers to gradually improve the pen-holding problems and ensure that this pen gripper set is suitable for users of each age. In addition, many writing posture errors are actually determined by the curvature of the palm, so we unique designed a palm fixer to solve this issue that has always been ignored. This posture correction tool fits on pencils, primary pencils, pens, crayons, markers, paint brushes, and any kinds of tools diameter within 0.35". If you or your family need handwriting support, come and try it, it can help you solve all problems.