Brake pressure bleeder for the Chev.

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I make one like that to accept a small clear hose coming off of a small garden sprayer which I fill will brake fluid and pump it up to deliver the fluid while I am under the truck cracking the bleeders.
What you have would be great for blowing all of the bad fluid out before a fresh refill. I may have to dig out another spare cap and put an air fitting on it.