Shimano J04C Disc Brake Pad
U need theseif you wnat them with the fin - u can get the pads without the cooling fin
I'll admit I'm not in the middle of any big hills here, but I did experiment just after purchasing it
Just off the A61 (Wakefield - Barnsley road), at NewMillerDam, there's a short steep lane
The old road, before an easier route was cut
It's not much 60-70 yards long, definitely 1-in-3
I can start at the top, stationary, creep down at walking speed (both brakes) & even at such a short distance, the fins are barely touchable
On longer/faster hills, they'll surely make more of a difference