Vampire Hangers are installed while the gutter is being ran out.  They are placed on a 32" centers in the gutter.  The Jaws will hold the back of the gutter with the bar between the hanger's prongs and the top of the gutter.  A Vampire Hanger Tool will force the hangers prongs to pierce the back of the gutter. Then using the same tool as pliers, with the lower jaw under the prongs, bend the prongs up for a firm and permanent fit. 

.063" Aluminum used and the asembly of the Vampire Hanger is a custom, strong rivet securing the strong rivet securing the strap to the hanger. 

The strap can be bent to the desired angle when attaching the gutter to the roof.