■ GULL Mantis Dry Fins (with spring) [GF-2285P] Weight, balance, propulsion power, specialized model for dry suits. ■ Compare to Mantis Fins The large boot pocket makes it easier to put on and take off. No ankle weight is needed, but the fin itself is heavy. Therefore, it is recommended for divers who are confident in their leg strength and want more propulsion. ■ Weight comparison with Mantis Fins Mantis Fins (S:895g) Mantis Dry Fins (S:1,550g) By increasing the specific gravity of the sole part, the center of gravity is lower than the ankle weight that is attached to the ankle. Provides more stable water balance. When you normally use 17.6 oz (500 g) ankle weights.