PreSonus Eris E4.5 BT Studio Monitor w/ Bluetooth technology (PAIR) PreSonus Sale! from $229.95 $229.95 Qty. Add to Cart This item is currently on backorder but you can still purchase it now and we'll ship as soon as more become available. Qty available: 1 SKU: PREERIS4.5BT Out of Stock PreSonus Previous Next