PROPOSAL TO ESTABLISH A LOW FREQUENCY CENTURY CLUB AWARD (LFCC)
By Les Rayburn, KT4OZ

...

0-100Khz (VLF Endorsement): Award would be granted to those operators who
could verify reception of stations in 25 Maidenhead grid squares.

Endorsements

for each additional 25 stations.

76Khz (Amateur VLF Endorsement): Award would be granted to those operators

who could verify two way contacts with or reception of stations in 10 Maidenhead grid squares. Endorsements for each additional 10 grid squares.

...

136Khz (Amateur LF Endorsement): Award would be granted to those operators

who could verify two way contacts with or reception of stations in 25 Maidenhead grid squares. Endorsements for each additional 25 grid squares.

Good idea, but is does not agree with the 'official ranges' :
VLF = 3 to 30kHz
LF = 30 to 300 kHz
So the 75kHz UK allocation is actually LF, not VLF

73, Rik ON7YD