I've been doing reviews for years, I like to think I do good unbiased reviews and I've built a small following on my youtube channel (122 subscribers) and I've got a few freebies from a couple of places.
Pretty much any of the companies might and do do it, But you need to get established first. be known for posting good reviews of the companies products you bought and post them on social media on the companies sites etc, get a following, in other words do things to get noticed by the companies.
The companies get all kind of requests for freebies, the ones the get answered are the ones that look like they can help move product and create buzz.
Small and less well know companies and newer ones are places to start
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