This backrest may be attached to most wooden seats and may be stored under the seat when not in use. It provides comfort for long cruises or leisurely paddling and fishing. Installation requires some drilling: four 1/4" holes through the existing seat, drill template provided. Stainless steel hardware is included. Measures 12-7/8" wide with a 15 degree angle, offers lower back support without interferring with paddling. This design is patented by Essex Industries. It fits most widths from 9-1/4" to 10-1/4" seats from front to back.