Safemailer is a cold email automation platform that boosts the deliverability of your emails. For that reason, we restrict the email volume to – 1,000 emails / day / sender account & 100 emails / hour / sender account.
This helps in increasing your email deliverability, landing maximum emails in inbox – https://safemailer.app/how-many-cold-emails-per-day/
If you want to send a higher volume of emails, you can simply use multiple sender accounts in parallel.