Trinket's got a big sister in town - the Pro Trinket 5V! Pro Trinket combines everything you love about Trinket with the familiarity of the common core Arduino chip, the ATmega328. All have built-in USB and are comparable in price! The ItsyBitsy's especially are about the same size and have native USB and tons of pins, so they're a very close compatible. So while we still carry the Pro Trinket so that people can maintain some older projects, we no longer recommend it. Please check out the Metro Mini (ATmega328 5V 16 MHz), ItsyBitsy 32u4 5V 16MHz, ItsyBitsy 32u4 3.3V 8MHz or ItsyBitsy M0 3V 48MHz.