Mega 3d is a refinement of Zone 3d. We offer FFF, FH1, H12, 123, 246, 357, 468 and 6810 designs, see below for more information: FFF: Float + Float + Float F1: Float + Hover + Intermediate H1: Hover + Intermediate + Sink 2 123: Intermediate + Sink2 + Sink 3 246: Sink 2 + Sink 4 + Sink 6 357: Sink 3 + Sink 5 + Sink 7 468: Sink 4 + Sink 6 + Sink 8 6810: Sink 6 + Sink 8 + Sink 10 Mega 3d line specification and recommendation: Size weight Length US rating Euro Rating 475 475gn 32.2' 500 500gn 33' 525 525gn 33.8' 500 500gn 34.6' 525 525gn 35.4' 5/6 6/7 550 550gn 36.2' 6 7 575 575gn 37' 6/7 7/8 600 600gn 37.8' 7 8 625 625gn 38.6' 7/8 8/9 650 650gn 39.4' 8 9 675 675gn 40.2' 8/9 9/10 725 725gn 41.8' 9 10 775 775gn 43.4' 9/10 10/11 825 825gn 45' 10/11