What is this component ?

[ArereDin]

I have to build a Lifi emmiter/receiver for a school project, i already have a picture of what the final result should look like and i don't recognize one of the components.

I'm pretty sure the component is part of the receiver part.

The light we receive shines on a photodiode, the signal is then amplified and fed into an arduino uno that converts the signal to bits.

Here is the component (red arrow pointing to it)

[calmtron]

Polymer film capacitor.