You dont have to buy just Shimano branded housing , aftermarket black housing is sold by the foot at Bike Shops.
shift housing is a low compression linear bundle of wires on end.. typical brake housing is a tight coil of square wire..
Now for mechanical disc brakes, they make a housing like shift housing but add a braided sheath of Kevlar outside,
To cope with the higher forces of pulling the brake levers hard .. that you could use for both..
Jagwire a brand, now exclusively through QBP at your bike shop with a dealer account with them.
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