The old Cateye LD600 was a great rear light, and the LD610 is the logical evolution of that design.
Powered by two AAA batteries housed inside a well sealed and well made unit, its light comes from five LEDs each with their own lens 'nest'. The Flex-Tight mounting as found on other Cateye lights is quick and simple to use, not to mention secure and durable.
The sealed rubber switch requires you to push and hold to turn it off, meaning you cannot accidentally kill the light - single pushes simply cycle between the flashing or constant modes. With the LEDs mounted further out than the old LD600 this light is more visible from wider angles, and also offers longer run times; we managed just under the claimed 30 hours of constant light with 29 hours and a few minutes, but longer than the claimed flashing time of 60 hours with just over 61 hours.