This is truly a unique product. Our Aphidius is reared on Green Peach Aphid. We allow the wasp to emerge, feed and mate before we individually aspirate them into a bottle. We have found that this technique: maximizes the vigour, by allowing them to feed immediately after emergence; maximizes the efficacy, by increasing mating exposure; eliminates the likelihood of inclusion of Hyper-parasitesIn addition, and perhaps most importantly, this product is never cold stored, insuring that their searching ability is maximized.If you are using this product as a substitute for other Aphidius products, you should be aware that there is a significant risk that if this product is used at the same rate, over-parasitism may occur, leading to cyclical control. This product should be used at about 1/5 of the rate you are used to.