MailChannels offers two distinct email infrastructure products for hosting providers and developers/SaaS platforms. **Outbound Filtering (for Hosting Providers):** A security-focused outbound email filtering platform that scans each outbound message before SMTP transmission. It detects compromised accounts, automatically isolates abusive senders, and stabilizes shared IP reputation. It is compatible with cPanel, Plesk, and WHM environments, and is designed to protect large-scale shared hosting infrastructure from spam outbreaks and IP blocklisting. **Email API (for Developers and SaaS Platforms):** A transactional email delivery service built around a SendGrid-compatible JSON API. It provides sender-level isolation, pre-delivery spam validation, and high-reputation IP pools. Multi-tenant controls include sub-accounts, usage caps, per-tenant sender reputations, event webhooks, per-tenant API authentication, and sender-level throttling. **Core Design Principles:** - Enforcement is applied at the individual sender level, not at the account level, avoiding tenant-wide service interruptions. - Pre-delivery filtering prevents spam from being transmitted, reducing the risk of IP blocklisting. - IP pools are maintained at favorable reputation ratings per Cisco Talos data. - The platform is not intended for bulk marketing, CRM, list management, or newsletter tools.