This is exactly how to mount a light BALDR on the Glock 43X

The factory Olite Balder only fits the standard width pick rail so it fits the Glock 19, the 1911 etc. But yeah, so what you need for a subcompact size gun frame is this OEM Part from Olight.
So this one here will fit the Glock 43X and this one here will fit the P365.
If you have a PIC Rail 365 grip frame then you can just use this one for the Glock 43.
There is no QD lever on this one so it sits flush and it doesn't have any sharp edges.
When you index your thumb on it just make sure you tighten the screw because if you don't it will get loose, and the light will fall off when you shoot.
So these adapters right here are compatible with Olight, Balder Mini and other compact sized lights with the slider mount.
And if you already have these lights and all you need is an adapter, this will save you lot.
Watch the video installation here: