The total height of a AIO liquid cooler consists of the radiator + fans, with radiators usually at 30mm (H) and fans at 25mm (H). For liquid cooling config Steck ver 2 + tophat, you can still use 30mm tall radiators, your solution is to use 15mm height fans ONLY.Would it be possible to create 2 variants of the top hat? Many aftermarket AIO come with +50mm height with radiator thickness and fan height added together. It would make more sense to let buyer choose the between smaller and taller top hats rather than be forced to buy 2. Also, 1 tophat vs 2 tophats aesthetics.
I have been waiting for case like this (bottom & top fans) and planned to use be quiet! Silent Loop 2 240mm (h=52mm) with the case. But I would be forced to buy smaller fans or 2 tophats to be able to use this AIO. Another popular AIO Kraken X53 seems to be h=56mm. I believe that I'm not the only one asking for taller top hat since there are just a few <25mm AIO radiator (MasterLiquid Lite 240, Eisbaer Pro Aurora 240, Eisbaer LT240) available on the market. And with <25mm rad height I refer to use of 25mm fans with the radiator.
How about second version of tophat with plus ~10mm height? Would be more than enough for many and buyers would get ton of more options to choose AIO.
Guess cost of 2 extra fans is a non-issue for SFF enthusiasts. Thin profile fans should be pretty standard procurement for SFF builds. You won't go wrong with Noctua fans.
There is no plan to make top hat or the main case taller to support 25mm fans. I have been receiving feedback to make top hats thinner, I am not going to now go back to make it bigger again