Commentaire sur Rois 2 12:5

The half-shekel [given by every male over twenty,] and donations representing the value of one’s age. Two types of money are mentioned here. “Everyone who passes the numbering,”³Shemos 30:13-14. [The first type is] the money of anyone who passes the numbering, i.e., the money of the annual shekalim, about which it is stated, and [the second type is] anyone who volunteers his own value, i.e., one who says, “My value shall be incumbent upon me [to donate].”⁴See Vayikra 27:1-8.

All monies that [a person’s heart] inspires him, etc. E.g., one who says, “I obligate myself to donate a maneh for making repairs to the Beis [Hamikdosh],