The CC2 Cushion Gooseneck Coupler is furnished drilled for use on trailers with a safety through pin. However, the pin cannot be used because of the internal mechanism of the CC2 Cushion Gooseneck Coupler. Instead of using the through pin, the CC2 is furnished with a studded collar to safely lock the unit in place. The CC2 is okay for trailers with no through pin hole and two set bolts.
If your gooseneck trailer has a coupler brace less than ½” above the through pin hole in the coupler receiver tube, the CC2 will not work. You can use the CC4 which is the same except has a 9” off-set. Below is a photo of the CC2 minimum brace clearance. (If the trailer gussets or safety chains are in the road of the clamp use the CC4 instead of the CC2)