Spektrum Firma 100A Brushless Smart 3s Esc W 3900Kv Motor & Fan/Heatsink #10329 September 10, 2023 admin Spektrum Firma 100A Brushless Smart 3s Esc W 3900Kv Motor & Fan/Heatsink #10329. Condition is “Used”, marked as used due to being removed from a new rig that was parted out and it not being in package. Please view other rc items.