MCR-QP Stackable Radiator Series Released

[3Z3VH]

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I'm sure a designs that fits both 25 and 37 mm fan spacing is possible (Koolance does it with the RAM fittings, so does BitsPower with the D-Plugs, using a slightly different solution), it's a permanent fixture (only the O-Rings are perishable, and those are really easy/cheap to source), and a much more elegant solution.
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The SLI Bridge I posted looks like it would fit for both 25mm, and 37mm...

At its shortest (18.0mm), it barely fits for a 25mm fan (18.4mm spacing), and at its longest (30.0mm), it could theoretically fit a 37mm fan (30.4mm spacing) with only a .4mm washer on one side of the fitting.

One of the obstacles is the QC on the rads themselves (as mentioned earlier in this thread) which would mean the fittings might not line up 100% if they were hard mounted as opposed to tubing.

Sounds to me like there is a market for a flexible D-Plug design... If this is even truly an issue, then all it would take on Swiftech's part, is 'binning' their radiators for the "Premium Stack" model... make sure the radiators they sell in that kit meet the tolerances required to square up that connector.