【UP to 32 SPM-4Relays】One SPM-Main connects up to 32 SPM-4Relays. Each relay includes 4 isolated channels for organized and scalable device control. 【20A per Channel】Each channel supports up to 20 amps, making it ideal for high-power devices. 【Overload Protection】Automatically cuts off power during overloads to protect your devices and ensu