If he is accurate with the description, it has to be an Estes cone. Nobody else uses the BT-60 nomenclature other than eRockets and they only make balsa cones. However, I don't recall an Estes cone that looks like an oversized Alpha III cone. I have to assume the BT-60 comment was to generically designate a 1.6x" tube.

Maybe the Sprint XL cone?

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