I got the infor for you...here it is: armforte.com (207)884-8226 PO Box 61 Levant, ME 04456 Attn: Mack Gwinn Mack Gwinn is the person who developed a quick-change barrel system for the Ma Deuce .50 BMG currently used by NATO. The inventor of the Counterpoise System is James Sullivan, Eugene Stoner's partner. Hope this helps! The old info I have states the price of the system at $189.50. Good Hunting!