PLB and Lifejacket options when submitting Flight Plans

I've read through the CAA leaflet/blurb about how to submit a flight plan form but am non the wiser.

I typically fly abroad/over water with

a) A PLB - the Kannard XS-4 which is 406MHz only

b) Reflective lifejackets for all crew which have a whistle, light and inflation

c) A covered inflatable liferaft

I don't carry a portable two-way radio. The aircraft has no ELT fitted.

Lifejackets have an option for UHF and/or VHF. Does this relate to the PLB?

I've entered maritime survival equipment and added details of the liferaft (colour, covered, capacity etc.)

Any other boxes I should fill in?

What would you typically write in the box for "Survival Remarks"

Thanks in advance

DavidC