Hello @cisco_Meraki, for 300 devices you'll require 300 SM licenses. 1 SM license allows you to manage 1 device from within Systems Manager.
There is no other hardware or licenses required to be procured to have the ability to use all the enterprise features from Systems Manager, You'll just need to pick whether you want to license the devices for 1, 3, 5 or 10 years.
Eliot F | Simplifying IT with Cloud Solutions
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