It refers to consistent FX points pricing spread which is the basis for the interbank market functioning. This pricing ensures that the spread of the price, rather than the volatility spread, is always consistent. The prices of standard options with a delta below 0.5 will be less sensitive to volatility. If the same volatility spread is used for a 0.5 delta option and an out-of-the-money option, the price spread on the low delta option will be decreased (all other variables held constant). As a result, the volatility spread for low delta options will be larger than the volatility spread quoted on at-the-money options.