Consequently, five types of fusion through collision can be discerned in the partition, corresponding to its five measures of opacity (ovyut):
Fusion through collision against a complete partition, which is formed with all five levels of opacity, gives rise to returning light that is sufficient to enclothe all ten sefirot – that is, until the level of Keter.
When there is fusion through collision against a partition that lacks the opacity of the fourth level, and has only the opacity of the third level, the returning light that it raises is sufficient to enclothe the ten sefirot only up to the level of Ḥokhma and does not include Keter.