Type of Plastic for outdoor enclosure

I have a Rachio Outdoor Enclosure that I keep locked with a keeyed padlock. Well, I lost the key and resorted to grinding the shaft off. However the shaft heated up enough to melt through the plastic ring. Does anyone know exactly what type of plastic this encolsure box is made from?

To be clear, this is the one I melted.

I’m thinking I could plastic weld a new loop for the lock. Its not mandatory that it be locked but it would give me peace of mind.

Thank you and please everyone stay safe and healthy.