Fortigate with Fortitoken

Does anyone know what is the max number of Fortitoken supported by each model? Is it only bounded by the Fortitoken Model in use by assuming the Fortigate model can support those concurrent SSL VPN Users together.

For license wide, I only aware it need to purchase Fortitoken per user. Do it need any additional license on Fortigate for pure 2FA VPN usage?

Thanks!