Due to the four flat sides on the lead, its virtually impossible for the carp to roll this lead on the bottom. This means the carp has to move the whole lead so feeling the full weight instantly. Carp up-end to feed sitting in water in an almost vertical position. If they pick up your hook bait and right themselves, the shortness of the lead means it will be picked up off the lake bed very quickly. The carp now has the hook in its mouth hanging under which is all of your lead - no resistance to feel the weight almost immediately.