Adding tags to ec2-Snapshots via powershell

I am trying to add tags to snapshots within AWS EC2 environment using powershell so that i can tag them for use down the road and some graduated snapshot retention.

I can manually create them through the console but for the life of me cannot find out which cmdlet to use. The best I've able to manage is edit-ec2snapshotattribute but that does not appear to be what I want.

I would rather not use the 'description' if possible during the creation of the snapshot as that is being used for other items