Daldorado DPE-16-BO 16" Bone Perpendicular Grate Perpendicular perimeter pool grating remains a very popular choice. Daldorado recommends perpendicular grating to be installed straight only for safety purposes, as when used for a radius the grate openings no-longer meet the requirements for finger and limb entrapment, where gap openings shall exceed 8mm. Available in standard 12”, 14” and 16” widths. Hand holds and curb angles available for true ledge support (radius or straight). Easy and worry-free installation.