I love these jackets, but sadly like most other cycle clothing manufacturers, they believe that us plus size cyclists do not exist, therefore are not worth providing the larger sizes.
I have mine on my rack at the back as I usually have a top bag on it so the seat post is obscured.
I remember i tried some of their Jackets/Gilets when
Proviz first started selling their products even though they had a very limited range, Even though the sizes were in the 'bigger' ranges, they still felt about two sizes too small and i sent them back. They charged me for returns despite a big flash banner saying "free UK returns" but after consulting their CC they refunded me postage via paypal.
Nice Jackets though, Just shame about the sizing/sizes
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Ive always tried to have a blinker on the back of my helmet (Blinker - not a blinder!) as It widens the range or angles at which i can be seen
Heres how I have my Kask helmet set up, pretty straight forward and easy
Its a Topeak Redlite Aero USB so its not the brightest but it gives 180' visibility so even if i turn my head to check whats coming up behind me, you can still see it. The light fit just perfectly as its the right length/girth to mount flush against the actual helmet and it uses the strap thing at the back of the helmet (pictured...)
To keep the light in line with the rest of the helmet. Theres supposed to be a small section at the back of the topeak like where you can slide a slab of rubber to help hold it in place so it doesnt wobble about when attaching to a seatpost but by not installing it, the back of the helmet is 'countersunk' into the back of the light.
On the days where i do finish work pretty late in the evening, seeing another cyclist with a blinker on the back of his or her helmet definitely makes them more noticeable in my eyes at least.
I measured the back of the helmet and looked around for ages for something that would just slot in and look as if it was part of the helmet. (you need a light thats 15cm, most similar lights are 16-17cm so the light doesnt sit flush with the rest of the helmet at leaves a small gap because of the angling of the helmet)
I would prefer it was a little more low profile as it sticks out just a little too much for my taste.
Sometimes i have big Tescos or Sainsburys lorries on their way to drop supplies off at their stores roll up behind me. I doubt the driver would of been able to see the light thats attached to my seatpost from up that high so its always peice of mind knowing they know im there.