Ports ends for inside speaker box with smaller diameter , these are 3d printed from PETG and made heavy duty, available in 3,4,6,8 and 10" sizes, fits all schedule 40 pvc and can be bonded with pvc cement, weld-on #3,#4 and #16
THESE ARE NOT FOR PLUMBING, THESE ARE FOR SPEAKER BOXES.
MADE IN THE U.S.A.