NAF off deet , Lincoln Classic Fly Spray , NAF off extra.Derby house fly rugs are good and not too highly priced I make my own fly spray :
20ml citruanella oil
100ml white vinger
50ml meths spirt
A drop of washing up liquid
and lots of strong tea!
= fly spray!
I find the gel types work much better than the sprays, my section a rips his fly rug and wont keep a mask on. I also bath him regualry in dermoline insectidcidal shampoo which help and as he is clean the flys are less attracted! He lives out overnight and comes in at lunchtime for my daughter to ride in the evening and has minimul flies on him when i catch him in, the others in the field seem to be caked in them so must be doing something right!
I find roll-ons to be the most effective (and most convenient around the face), but I tried Horsewise 'No Flies Naturally'(?) recently and found it to be one of the best I've used.
I switched from NAF off extra to a homemade one:
5 drops each of citronella, tea tree, ecalyptus and lavender oil,
2 parts white vinegar to 1 part water.
It's really made a difference and a lot cheaper!