Cheap And Discounts Dual Op Amp Pre-stage 3x DC Amplifier Board PCB Small Practical High Quality Board JCDQ41D For NE5532, OPA2134, OPA2604, AD826 Wholesale. Buy Directly From Merchant House Improvement 22 Store. Enjoy ✓Free Shipping Worldwide! ✓90 Days Buyer Protection. ✓Easy Return. ✓Money Back Guarantee.