Do know people who should be involved in the PMC, but aren't? Invite them to join you at the PMC Open House. On Oct. 19, PMC riders, volunteers and their friends are invited to check out the PMC headquarters, mix and mingle with the staff, learn more about the event and how to become involved. PMC merchandise will be on sale at discounted prices of up to 60 percent off. PMC 2011 Heavy Hitters are also invited to the Open House to pick up this year's Heavy Hitter gift: an official PMC New Balance back pack. There will be refreshments and PMC sponsor Harpoon will be on hand pouring beer. The open house is from 3 p.m. to 8 p.m. on Wednesday Oct. 19 at the PMC office, 77 Fourth Ave., Needham.