https://www.amazon.com/Pink-Lizard-Shoo ... 8657287&sr


Comparing to my black unit, I think the spring on this one looks a little thicker. Plus the name is really confusing "... tank upgraded model..". Not sure if it's implying it's for tanks we upgrade, or that this unit itself is an upgrade to a stock unit.
Just trying to get the most fps, so I figured before adding a set of washers, etc. to strenthen my stock unit, it's best to start off with a stronger unit, and then do the upgrade.