This wide neck 8oz borosilicate glass baby bottle is designed to grow alongside your little one. With a variety of nipple sizes and sippy caps our bottle adapts to your baby's changing needs. Our vented hard sippy cap (12 months) includes a fitted silicone valve that helps control flow and allows cap to screw on tightly. The wide neck makes it easy to fill and clean while the silicone grip makes it easy to grip and easy to love.