Yup, it looks like the flexi tails terminate in a female 1/2" BSP
Normally I would stick a full bore compression service valve on the end
of your pipe, take off the other nut and ditch the olive, and then
screw the tail directly onto the valve. The flexi has a rubber washer in
it to make the seal.
 Remember to use the right inserts on the plastic pipe when using
Not the most useful photo, but you can just see a flexi fixed onto a
service valve in the way described here:
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.