If memory serves me correct, we installed a chain link fence and added this deck rail around the pool to satisfy the request of our customers insurance company.
The deck rail here is a design based on the Kennedy fence section. The bottom and top horizontal rails are 1 x 4 with facing edges having a routed bead. The top rail is a 1 x 4 board with both side having a routed bead. The 2 x 2 members are spaced 3 apart and are sandwiched between the 1 x 4 horizontal boards.