The Shimano PD-T400L is an a clipless pedal like many of the others I have on my bikes - in that it has a double sided entry, tension adjustor for how tight you want to be clipped in - but is also has a plastic cage on which reflectors are integrated.
Along with the pedals you get a pair fo 5M-SH56 cleats and the pedals weigh in at about 500g for the pair. There isn't really a huge difference in weigh between these and other Shimano SPD pedals I use.
One benefit from these pedals - apart from the built in reflectors - is that you can use the pedals with normal shoes or trainers if needed. I don't think that this is something advertised on the tin as it were however you can. I have used them quite happily with trainers and smart work shoes.
These pedals aren't for everyone and most cyclists using clipped in pedals riding at night do not have reflectors on their pedals. I do wonder whether the law needs tweaking for this reason - there are so many other reflective bits on cycle gear. At the moment I have a pair of these on both my Brompton bicycles and I plan to definitely get a their set to go on my Surly Disc Trucker. I do lots of night rides and just like the idea of the extra bit of reflection
They retail at £39.00 but shop around and you can probably pick them up for the £25 mark.