"Zendle" should be Zendl, right?
They make sights for CZUB, so OEM adjustable rear sight is Zendl also, with CZUB branding.
I am using it with Zendl 2,4mm (0,095 in) front sight, it works great. Rear notch is 3mm (0,118 in)
It works great, I have set it months ago, it holds zero very well.