A-Star 32U4 Prime LV microSD (SMT Components Only).The A-Star 32U4 Prime LV is a programmable board based on the ATmega32U4 AVR microcontroller and arranged in the common Arduino form factor. The A-Star Prime offers many additional features and improvements over competing products, including superior power management that enables efficient operation from 2 V to 16 V (though it requires at least 3 V at start-up). This configuration of the A-Star 32U4 Prime LV includes microSD support and does not include any through-hole components; it is intended for those who want to customize the way it is assembled.