Tekiac is selling a special mounting aid tool for attaching the new B+W Ultra Slim Filter Series on Leica Q3 43 cameras (this is the first B+W filter that can be used in macro mode and with the Q3 43 lens hood).
You can use the discount code LEICARUMORS to receive a 5% discount when purchasing from this link.
Additional information on how the tool works:
Other Leica Q3 43 accessories:
The new Leica Q3 multifunctional protector seems to be recalled
Freewell has new Leica Q3 43 accessories: Real Lens Hood and Thumb Grip with Cold Shoe Mount