This item was created by me using a 3D printer and handcrafting. It has been used successfully in actual fishing. The main body of the plastic (PLA) is 3D printed, while the stainless steel eyelets and the spring for opening and closing the cage are handmade. Images 1-3: The cage is designed to open simultaneously upon water entry. It's designed to open as easily as possible within a range that doesn't interfere with fishing, so you don't waste time with the cage not opening. Also, the spring is designed not to bounce up excessively to prevent the leader from tangling. Images 4-5: There is a screw-on lid on the bottom cage, allowing you to insert weights of your choice. Weights of a certain size can be inserted directly. I use a pear-shaped weight directly. Weights that don't fit can be shaped with a hammer without melting them. The weight is approximately 50-55g. Images 6-7: The concept is large capacity, and it feels like it holds more than twice the amount of chum as a commercially available Apollo Ippatsu Cage. The diameter is also large, about 5cm, making it very easy to put in chum. You can attract fish by scattering chum all at once with fewer casts. It's also perfect for live bait fishing. Images 8-9: During a single test fishing trip (about 3 hours), I caught two 45cm sea bream! ヾ(*´∀`*)ノ Image 10: This autumn's catch! Blue-backed fish and rockfish are being caught! Please understand that this is handmade, so there may be individual differences. The weights and Apollo Ippatsu Cage shown in images 5-7 are not included.