Kuota++ is data quota top-up that can be used to access the Internet anytime. The usage period is longer, that is as long as the Tri card/Internet is still valid, and the data will be accumulated. It means your quota would not expire in a month.
Nelpon++ is minute top-up to call fellow Tri card users or other operators. The usage is longer, which is as long as the Internet/Tri card is valid, with accumulated phone minutes. Nelpon++ can be used for any Tri SIM card.
SMS++ is text message top-up to be used to fellow Tri card users or other operators. The usage period of SMS++ extends for as long as your Internet/Tri card is valid. The number of text messages will be accumulated. SMS++ can be used for any Tri SIM card.