The HDF float is a weighted float made for the purpose of being able to cast further without using excessively heavy weights. The shape and added flaps allow the float to go further than what would usually be possible.
The product can be used as is during the day but is also made with a slot for a 7mm battery/chemical light so it can also be used during the night.
The floats come in three sizes: 6, 10 and 15. You match the float with 20g, 30g and 50g respectively (+- 5g).