LIF. Twins are stylish, wearable wrist/ankle weights that have been re-designed to put a modern spin on the commonly sand-filled wrist or ankle weights. They are made of cast-iron bars which are wrapped in a smooth, soft-to-touch silicone exterior for added comfort. Bound with an athletic elastic strip, the silicone-cladded cast iron bars are adjustable and can be moved along the strip to find what is most comfortable for you. The weights are also secured by a velcro closure which can be adjusted to fit any wrist/ankle size.