In a nutshell, electro point clips are a quick, easy and affordable solution to de-isolating points (turnouts) ready for DCC operation.
If you're familiar with model railways or trainsets, then you'll know that when you switch your points, the route not selected becomes isolated. In some cases, that can be a problem when converting to DCC as the whole point is to operate any train, anywhere, and at any time, and isolated sections of track would prohibit this.
Most railway modellers will simply run a power feed to connect to any track placed after the points. But if you don't like the sound of extra wiring, electro point clips will provide you with an excellent solution.
You are guaranteed to be surprised at how simple the clips are when you see them, they are literally just a bent piece of strong but fine metal that clips between the rails of a turnout. But that doesn't mean they are not effective and many modellers are happy to use them on their DCC layouts.