Thought this might be of interest to others…

I just installed a lockable filler cap from Newton Equipment; they supply the original filler cap for the PlusFour (their name is stamped on the underside), however they have just started producing a lockable version.

It is the Aero 200 Centre Cap - Locking, Silver - CA-AA-128 ( A2SL ) available to order online directly on the Newton website.

https://www.newton-equipment.com/aero-200-range.html

Fits perfectly my MY22 PlusFour, see pictures. Second pic shows lockable one on the left, original cap on the right.

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