17 C.F.R. § 274.51
Form N-18F-1, for notification of election pursuant to § 270.18f-1 of this chapter
(a) This form shall be filed with the Commission in triplicate as the notification of election pursuant to § 270.18f-1 of this chapter by a registered open-end investment company to commit itself to pay in cash all redemptions requested by a shareholder of record as provided in said section.