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Salesforge AI
The cold email infrastructure trusted by 1,200+ agencies. Pre-warmed Google and Outlook inboxes, fully configured and ready to send — from $0.35 per inbox.

Managed Hosting for developers, entrepreneurs, and businesses like yours
Website, pricing, platforms and company facts side by side.
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| Website | puzzleinbox.com | opalstack.com |
| Pricing | — | |
| Company | 2023 | — |
| Listed in |
In their own words, as submitted to SaaSHub.


Puzzle Inbox is a cold email infrastructure provider offering pre-warmed Google Workspace and Outlook 365 inboxes, fully configured and ready to send in 24–72 hours. Trusted by 1,200+ agencies and sales teams worldwide, with over 70,800 active inboxes deployed, Puzzle Inbox is the go-to solution...
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Warmup Inbox is a tool that automates the process of warming up your email inboxes, raising your sender reputation and inbox health automatically.
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Apollo’s predictive prospecting, sales engagement, and actionable analytics help the teams to reach its full revenue potential.
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Personalize Cold Email Outreach at Scale to 10X Pipeline
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