Skinny I had a 4' on top of my 23' Parker pilot house which put the tip 10' above the water about 12mi was the best dist. I replaced it with 5225xp 8' I can tell you there is a world of diff in 4' between a 4' and 8'. I was 5-6mi west of Rattle Snake on Sat a guy calls his buddy give location(cord#) I ask him to repete # he was 2mi se of Virmillon weather bouy 20+ mi from me.I have a Standard Horizion it's built into gps/sonar (cpv550) I have always had good service out of S/H. I have 2 Shakespear 1' extension if you need to raise your antenna list $40@ pm if interested. I could save time by saying go 8' if you can