I am looking to buy some waterproof membranes to make a housing for my AudioMoth devices.
I have enquired with https://voir.en.alibaba.com/product/60380452525-801219240/e_PTFE_acoustic_membrane_for_speaker_and_mic_IP67_waterproof_sticker.html as suggested by another forum post. It is possible to purchase a small number but the shipping is $25 as I think they are shipped from China (I am in the UK).
I have also come across http://www.porellemembranes.co.uk/en/products/porelle-industrial-and-scientific/porelle-acoustic-vents/#contact . They are UK-based so I would avoid the large shipping cost, and they claim that their membranes are better than e-PTFE membranes (like the Voir product) as there is less dB loss.
Has anyone used the second product or have any opinion on which would be better?