CO2 cartridge under saddle mount

I want to down size my saddle bag, but still want to keep 25g co2 cartridges. Given the saddle bag I got is hard shell with quick release, it does not come with external strap for the CO2 cartridges. Therefore, the only option for me is to mount it outside of my saddle bags under the saddle. You will need two M3 x 10mm screw + nut set for the mount, but they should be very easy to find on amazon or aliexpress if you do not already have them lying around. 

I just got the bike so I did not test the rigidity of the clip, however, I will strongly advice you to print it with at lease ASA if you do a lot of outside riding. Will update later in the season once I got some miles on it.