Do We Need A Tag For XRP Transactions?
Usually, institutions with large client base (e.g. Exchanges, etc...) may require destination tags for XRP payments as they usually use a single XRP address to minimize the need for reserve requirement (https://developers.ripple.com/reserves.html). And because that, they need the tag to identify which customer the payment is for.
For personal XRP addresses (CoolWallet S XRP Addresses), you do not need a tag as the XRP payment goes to a specific address (one recipient). However, if the exchange which you are sending the XRP from mandates a tag for outgoing XRP transactions, you can simply enter any number from 1-9 in order to send the XRP to your CoolWallet S.