Redbirds is right, a one way valve means you just put the overflow into a bottle and gently ( to stop the hose coming off ) punp the handle with the new fluid until refreshed whilst keeping an eye on the fluid level.
as an alternative i use a one way plastic aquarium valve, non corrosive, requires very little pressure to operate, transparent and available from aquarium suppliers every where.
I just flush it out with water afterwards, plastic aquarium hose works fine but silicon hose is a bit more flexible to use on different size bleed nipples;
That leaves only the fluid in the calipers to be changed and i haven't found an easy way to spread the pads and expel the fluid out........
sometimes i get lucky, and the more i practice the luckier i get
and; It's always something simple......just not always simple to find.
2020 cb1000r chromos red
2010 cb1100 candy red
2006 cb919 hornet black
1977 cb550 k3 1st owner