Or any other file sharing website for that matter, but at least use something more secure from a more trustworthy company, such as https://send.firefox.com/ (never heard of sendgb.com).
Yes firefox is good option. Sendgb is from Estonia. Sendgb allows file transfer up to 5 GB. File are storages up to 90 days for free. Nobody knows which one is more safety.
Sometimes big services have more security problems...like Dropbox, wetransfer etc...