Hi ericlebouffon, You will not be able to fit two radiator tails in 15mm. Buy the narrower radiator, get rad valve tails and see how much space you have - you may need to buy some radiator tail extensions or adjustable valve tails. Regards S
The valves come with the bits that go into the radiators, they don't come with radiators, you can buy a special Allen key to fit the parts, normally you would remove from old radiator put some new PTFE tape on them and fit in new radiator.
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