Plugs you put into brake cable

I think you are looking for olive & barb / connector sets. You need to get the right one for your particular brand / model of brake as they vary.

I think you mean one of these:

Reverb stealth barb connector. You screw it into the cable to seal it off. Makes internal routing less painful

https://www.tradeinn.com/bikeinn/en/rockshox-stealth-barb-connector-reverb/136091602/p?utm_source=google_products&utm_medium=merchant&id_producte=3255726&country=uk&gclid=CjwKCAjwiOCgBhAgEiwAjv5whPAZKSPyPwhA1OA6A97vYnidSltW_vxLiHMw3OJ9gq69wsixnYU-kRoC6DQQAvD_BwE&gclsrc=aw.ds

I just use a spare barb with a nail pushed in tight then trim off the point, makes it magnetic if the barb is brass to make routing easier, assuming your talking about routing without losing fluid from the hose when going inside the frame.

I just drained the fluid and bled them properly afterwards. Odds are you'll need to do it anyway.

I think you are looking for olive & barb / connector sets. You need to get the right one for your particular brand / model of brake as they vary.

I've used Shimano in SRAM and SRAM in Shimano, others may vary but they're all basically doing the same thing (crushing the olive to make a seal), SRAM's system is I suspect a little quicker on a production line as it screws together rather than needing a press to get the barb in.

Plugs? What, firteen amp?