The internals are made out of plastic.
As said before, using the double-triple l/h on a double only, due to Shimano's outer very likely to get substantially compressed, when moving "small ring-->big ring" the shifter goes over its natural position for two rings only use, and the mechanism gets stuck. In fact, is always hard to click on th inner lever to release the cable. If this happens, the inner lever should not be used, but the cable loosened from the fixing bolt, the setup again with the right amount of tension.
AFAIK Shimano was giving warranty on them
The internals are made out of plastic.
As said before, using the double-triple l/h on a double only, due to Shimano's outer very likely to get substantially compressed, when moving "small ring-->big ring" the shifter goes over its natural position for two rings only use, and the mechanism gets stuck. In fact, is always hard to click on th inner lever to release the cable. If this happens, the inner lever should not be used, but the cable loosened from the fixing bolt, the setup again with the right amount of tension.
AFAIK Shimano was giving warranty on them