The double-geared lifting mechanism of a crane.    From Wordnet, Princeton University. 

About 3000 of those investors were tipped into high-risk double-geared portfolios which fell into margin call late last year as sharemarkets crashed.    From Wordnik.com.  [AustralianIT.com.au | Top Stories] Reference

Like lightning double-geared.    From Wordnik.com.  [Beautiful Joe] Reference