Initally this product did great with knocking down the noticeable spiders. But it was crap with residual. The call backs on this product has been 100%, thus I've taken this product off my inventory shelves.
We live on a lake in Texas. The spiders are relentless. As I understand, spiders are hard to kill because they DO NOT groom their legs ... they must be doused with insecticide for it to be effective. I was using Demand CS and it worked. I switched to Onslaught due to the recommendation of the website. It might be effective on Martian spiders, but Texas spiders just thumb their noses at it. The Demand CS is currently in route.
I purchased this product at the recommendation of DoMyOwn for bird mites. I have been spraying Onslaught with an igr for over four months and it has not worked. This stuff is not cheap and I am very disappointed.
I have performed my own pest control for the last 15 years and this is the first year that I have used Onslaught. I have to say this has been the worst year for scorpions I have had and I have put more poison down than any other year. This stuff simply does not work. I live is the Phoenix area for reference. Buy Demand or some other reliable product