Hydro Cones Pool Toy in Assorted Colors PKG (2) These 12-3/4" long plastic cones are 5-1/2" dia at the bottom and taper down to 1-1/4" at the top, with handle cut-outs. Called Hydro Cones, you pull the wide end under the water and then witness the focused H2O explosion that blasts skyward from the skinny top. If that's not enough fun, just use them as pool-side traffic cones or megaphones to yell at the kids. We'll pick from purple, yellow, orange and green.