In my humble opinion, without any doubt the very best indicators out there are made by Kellermann, very very bright in use, but almost invisible when not in use, only 10mm diameter max, the lens diameter is 7.8mm diameter, they do an indicator version only for around £60.00 per unit, so £240.00 to do a bike with 4, or if you are really flush with money they do a 3 in one version with additional rear light, stop light and indicator for around £90.00 per unit, so £360.00 to do a bike, the model is Kellermann Bullet Atto, they are very good indeed, and so they should be at that price.