Over the last year I have really leaned into the Pentel Energel as my go to pen of choice. As was inevitable, I started looking around to see the best option for a machined pen for this refill. The 36 Click Pen by Autmog is that pen (when Brian makes it into a 0.5mm version), but getting something bespoke for this refill on such an elegant looking pen has now gone top of my list.