Both Tamiya and Gunze cement bottles “almost” fit in a 1x1 Gridfinity. Even more annoying is the fact that, except for this model by Alchemik, there seems to be no storage design for the hexagonal bottle of Tamiya Cement - aka Orange Cap. So, I took their model and designed a solution that works for my Gridfinity OCD needs:

• Two single bottle holders (2x1) - one short and one tall (which I use on my desk)
• Two four-bottle designs: A 2x3, for a more efficient use of space, and a 3x3 (for those with the symmetry strain of OCD)

They are not stackable, because I like easy access at a glance. 

Why four bottles and not three or five? Well, I only have four bottles.