"Tension is not enough and relaxation is not enough either. You have to use tension and relaxation together." - DK Yoo <br /> <br />E-mail: dkwcs@naver.com <br />Blog: http://blog.naver.com/dkyoo79 <br />Instagram: https://www.instagram.com/dkyoowcs <br />Facebook: https://www.facebook.com/systemakorea
