Michael's Fat Boy Silencer Gel Pen Black Michael's Fat Boy Silencer Edition Gel Pens feature a wide barrel for better gripping and comfort, which has a U.S. Patent. Each Fat Boy Gel Pen is crafted from U.S.A. aircraft quality billet aluminum bars and equipped with high quality retractable mechanisms from Germany. The Michael's Fat Boy Silencer Edition features evenly spaced holes throughout the pens barrel and has two rubber rings on their barrels for a no slip grip. Accepts both gel and ballpoint pen refills