 You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more
I use a pannier rack with bag so having a light on seat post is not an option.
So I would like to know which lights can attach to the seat stays. I want one on each side.
Can you bolt a light on the back of the rack? Quite a few racks have a hole for this, or you can adapters from companies like Topeak to fit a light to the back of the race. Probably a bit more secure and less prone to damage that a seat stay.
Aldi set. Got the rear on my seatstay
I have this one - small and very bright. Cheaper when I bought.
[url= https://www.merlincycles.com/moon-lx-70-rear-led-bike-light-72944.html ]USB light[/url]
Smart Lunar R1, bargain at 6.95 and comes with all the brackets to attach to seat post or seat stay.
The R2 is great as well, but not quite the bargain of the above (watch out for the USB version, the non-USB has more modes - the crazy random pulsating flash is very effective but doesn't feature on the USB one)
https://www.amazon.co.uk/Smart-Lunar-R2-Rear-Light/dp/B00452O6LI
Had a rack-mounted B&M Toplight Line for quite a few years:
[img] 
[/img]
The Bontrager Flare comes with a seat stay bracket. If you get the RT version and the ANT remote, you can use them as indicators and control the modes from the bars too. I have a set and they are ace.
Bueller
Got a link please?
Fibre flare!
Jacob,
Forgot to say, can also control them from certain Garmin models.
Complete with an acid stain, the hipsters would bite your hand off for one of these.
[img] 
[/img]
[url=http://]Lezyne strip drive[/url]
Like the every ready!!!!!!
I've run a fibre flare on the seat stay of my commuter for years. 1 each side would be very visible I'd say.
Nice one scuttler, i had a pair of those (one each side) on my Raleigh Grifter.
That everready was my first ever light set!