Anti-theft high foot Roof Bars

Been looking for a pair of Anti-theft high foot Roof bars that fit the rain gutter.

But all I've seen are the type that have a hand knob for clamping without any form of locking (anti-theft).

My Disco has the front bars alongside the Sun roof, but fitting bars to these are not much good for carrying a set of ladders.

Anyone know of a supplier for the Lockable bars as described above.

Thanks

Sorted........

Thule, do one.