Lambda-cy is 35 a gallon
PB08 is I think 85. Both go a long way in making ultrasaber and you can leave out the pbo8 but it doesn't last as long.
1 gallon of corn oil is the only other thing you need.
http://store.doyourownpestcontrol.com/pbo-8-synergist
Also other pyrethrums are cheap if you buy them where they are sold to apply to crops.
You can treat back rubs and/or spray them with a hand sprayer mixed with water orI have a 25 gallon atv sprayer on my feed truck. The get sprayed when they eat, they get a pour-on when they are worked and they walk under back rubs.
Use Diesle or corn oil on the rubs only spray with water.
I didn't read all the responses, just saw the one about ultra boss.
It and ultra saber are the same except the chemical. Don't use lambda on horses.