This is a high-quality yellow plastic trigger that can be attached to a 750ml plastic bottle. A spray trigger can be screwed on the bottle to spray chemicals on stains to remove them.Do not use any chemicals with this trigger that etches away rubbers or plastics, such as engine cleaners, thinners, alcohols, spirits or other aggressive chemicals. The result of the use of these kinds of chemicals will be that the spray trigger will no longer work due to the chemical damaging the internal mechanism.Only tighten the trigger head to the point where it has a finger-tight fit on the bottle. Numerous bottles have different designs and even though the trigger may be tightly fitted, the bottle would allow more space for tightening. It should not be tightened further, otherwise the mechanism will be damaged.