12 sq ft external top wing. Dimensions: CENTER SECTION 48" wide by 36" long. Side boards: LEFT 54" by 26" RIGHT 54" by 24". Standard offset of side boards is LEFT side board sticks out 12 1/2" from nose cap RIGHT side board sticks out 2 1/2" from nose cap. Position of side boards can be changed per customer request. Wing comes standard with a built in 1" wicker bill.