My First ever 3d model, excuse the side I had an incident during the print but figured id use it to show the infill.

I also havent printed the second spool holder so in one of the photos i hold the spool where it would be, anyway this device allows for holding/feeding of two filaments and has a hook to hold one filament when not in use or as a ziptie mount for easy swapping of filaments.

it lets You you to keep 2 spools ready to roll at one time or even better for people who have a dual extruder mod, personally I think it goes hand in hand and would say kinda inspired by this mod.

It works great and i feel some credit is due for the inspiration,
its called the direct drive mod (OOTBDD) as seen here
https://www.thingiverse.com/thing:5802023/makes

Only tested this on my aquila c2 with the OOTBDD but from what I can see it should fit other similar printers,

to install remove the 2 top bolts (pictured) holding the top of your frame off to slide clips in allowing you to fit onto the frame and then re attach the bolts, holder should slide right on in and will be a snug firm fit so it stays strong

Quick note: as mentioned there is a small hook/loop used for holding the filament this points down and so potentially takes a small ammount of space when making tall builds but we are talking from the top of the frame the hook/holder comes down about 10mm so it shouldn't be an issue realistically, that being said I havent yet tested an extremely tall print.

I also recomend cutting some bowden tube or similar loading tube to fit in the holes to a length of at most 29mm, its probably not required but makes for smoother loading/feeding during usage and a lot of printers often come with some spare so its free in most cases.