With due respect to Sberger, he is incorrect when he states that the Scoutmaster does not offer the peripheral ring clamp. The ring clamp most certainly IS available with the Scoutmaster. My local VPI dealer sells it, and it is shown on the VPI web site -- see this link for more info:
http://www.vpiindustries.com/master.htm
Note the wording at the bottom of the ad: available with periphery ring clamp and SDS power supply.
http://www.vpiindustries.com/master.htm
Note the wording at the bottom of the ad: available with periphery ring clamp and SDS power supply.