If you're talking about the one with the flat rubber pad on it then you're a better man than me if you can string that heavy a bow with it. The heavy two cup stringers from the Hill archery sells are what we use for the 80# plus bows but that flat rubber thing sets way to far from the limb tip for the heavy stuff in my opinion. If somebody out there has come up with a way to use them for heavy bows I'd love to hear it.