This spool extends casting distance by reducing brake force at the later half in casting. Fits to Daiwa 1000, 1012, 1025 and 1016 reels, T3(all models) and etc. Flat bottom, light-weight 15g spool to improve casting performance especially for relatively heavy rigs of 10g-28g 3/8-1oz. G1 grade duralumin. In MAGFORCE-Z Boost brake, rotor will pop out far only at the beginning of casting to prevent backlash, and then it retracts to the middle to reduce brake to add casting distance. The second half spring is 4 times stronger than the first half to do the trick. Compared to SV Boost spools, this Magforce-Z Boost spools have more weight, and it is more suitable for heavier rigs. You may cast long distance without fear of backlash with this spool. Casts great for heavier than 7g 1/4oz. 0.330mm(US12lb)-100m(110yds)