PERMITHRIN. Haven't had a chigger or tick on me this whole year, not one. I mix my own from concentrate and put in spray bottle - pre-treating my socks & pants extremely well and hitting all other clothes as well. one bottle last you the whole year....
I mix mine "TOO HEAVY" It's very easy to mimic the bottles you buy pre-mixed, very simple math. I think some of them (this is going way back in my memory) were something like .5% Permethrin. I usually have double the rate of the pre-mixed & soak my socks & pants - then letting them dry. Not recommending this for others since that's likely not on the label but that's what I do. Of course if your concentrate were 30% Permethrin - pretty easy to get your ratios of water to dilute to the same as a pre-mixed. I have zero ticks or chiggers on me - ever. Deet, deep woods off, you name it - all did not work anything close to what permithrin did in my years of using it.