The amount you can purchase for a recharge in Cuba is limited to a certain rate in CUP, set by ETECSA for those recharges sent from outside the country.
Visit www.fonoma.com to learn about the different recharge options. You will see the value for the recharge in CUP and its cost in USD or EUR.
The minimum for a recharge is the equivalent to 250 CUP and the maximum is 1250 CUP, for cell phone recharges, as well as Internet WiFi Nauta recharges.
During Cubacel promotion period, you must recharge the equivalent to at least 500 CUP in order to benefit from the bonus.
Here's the same idea, but expressed in EURO. Remember: the value in EUR fluctuates slightly since it directly depends on the EUR/USD international market exchange rate:
Choose the amount you prefer to recharge your contacts in Cuba.