Cap, Screw Ring, 28 mm for 16 oz, 450 ml bottle. This is the part the goes bad on the ratchet cap that uses the 16 oz (450 ml) bottles. If the bottle can not screw on straight this is usually the cause. We now offer an alternate bottle cap for this part now. This alternative part needs a new mounting bracket. Part Number 102-107189 contains the new cap and bracket. This new type cap assembly comes with the mounting bracket, tubing and fittings. It includes 1/4-28 couplers, tube nuts and ferrules to allow easy installation to existing tubing.