The Millennium Marine Shade Tree Fishing Umbrella Holder attaches to seat post under seat and is constructed of heavy duty, anodized aluminum. Easy installation, fits all standard boat seat posts. Swivels 360 degrees for maximum protection and simple locking mechanism locks umbrella in place.Note: Umbrella and seats shown for demonstration purposes only and not includedFeaturesAttaches to seat post under seatConstructed of heavy duty, anodized aluminumEasy installation, fits all standard boat seat postsSwivels 360 degrees for maximum protectionSimple locking mechanism locks umbrella in placeContains interior bearing, will not mar or damage postEasy, quick telescoping adjustmentCan also be used as a net holderFits Millennium Side Kick Double Fishing Seat (Side Kick and seats sold separately)Accommodates 1-1/4" to 2-1/2" shaft diameterMaterial: anodized aluminumSize: 16a ^2 L | 7a ^2 W | 2.5a ^2 H