One would think that such a thing does not exist. However, Hungarian fishermen invented the actual bait, a hybrid between classic coarse fishing and a carp ground fishing bait. A pop-up maggot attracts white fish better than a whole bunch of other expensive baits on the market. This is an excellent bait for coarse and feeder fishing that I have come across in a long time.
In addition to the pop-up maggots, there is also a line of bait for coarse- and carp anglers (from pop-ups to mixes for the feeder). Together they form one of the finest lines of fishing bait in Europe. Really worth trying!