Abstract: A bayonet coupling between a spray pump and a bottle of a substance to be sprayed provides a better quality fitting between the pump and the bottle and in particular a uniformity of the relative angular position between pump and bottle. The coupling includes at least one tooth projecting from the pump, and a tooth catch projecting from the bottle, a sloping wall formed in the tooth catch over which the tooth can be snap-engaged at the time the pump is fitted axially onto the bottle, as well as, formed in the bottle, a funnel-like passage through which the tooth is to pass as the pump is fitted axially onto the bottle, so as to orient the pump angularly with respect to the bottle.