Mailshake - Send up to 2000 emails per day. Automated follow ups, on-click emails, and integrations. Best for high volume sending. $59 / month.
Lemlist - Send up to 500 emails per day. Similar to Mailshake, but with lower daily limits and some additional features. Lemlist can automatically warm up your email domain and help you maximize deliverability. Best for just getting started with cold email. $29 - 49 / month.