The other day, when I bulk ordered 350 CO2 cartridges,
I took the opportunity to stock some rear lights as well.

These are COB rear lights,
and they come in four types: star, heart, bone, and circle.

The left side is the switch,

and the right side is a screw-on battery cover.
Battery changes are a bit of a hassle, but that's unavoidable when you're going for waterproofing.

The included velcro straps come in two sizes,
and if you use the longer strap (the image above shows the shorter one)
you can mount it even on pretty flat seatposts.

This light has an aluminum (probably) base with

a COB (Chip on Board) LED attached to it,
combining lightness and water resistance.
The circuit board and battery are housed in a highly waterproof body,
while the bulb itself is left exposed on the outside—a design
that should be essentially immune to water splash from wet-weather riding.

And it's quite bright.
It does seem vulnerable to wire breakage from bending the base section,
so that's something to watch out for.

Apparently the heart shape is popular with riders of a certain Italian brand,
and when people mention that, they usually get told by shops
"Well, what about a clover then?"
The COB section design has some limitations apparently,
since the elements need to be arranged in a single continuous line.
A . . . single continuous line . . . the Magic Kingdom . . . ugh!
My head . . . (→here)
I took the opportunity to stock some rear lights as well.

These are COB rear lights,
and they come in four types: star, heart, bone, and circle.

The left side is the switch,

and the right side is a screw-on battery cover.
Battery changes are a bit of a hassle, but that's unavoidable when you're going for waterproofing.

The included velcro straps come in two sizes,
and if you use the longer strap (the image above shows the shorter one)
you can mount it even on pretty flat seatposts.

This light has an aluminum (probably) base with

a COB (Chip on Board) LED attached to it,
combining lightness and water resistance.
The circuit board and battery are housed in a highly waterproof body,
while the bulb itself is left exposed on the outside—a design
that should be essentially immune to water splash from wet-weather riding.

And it's quite bright.
It does seem vulnerable to wire breakage from bending the base section,
so that's something to watch out for.

Apparently the heart shape is popular with riders of a certain Italian brand,
and when people mention that, they usually get told by shops
"Well, what about a clover then?"
The COB section design has some limitations apparently,
since the elements need to be arranged in a single continuous line.
A . . . single continuous line . . . the Magic Kingdom . . . ugh!
My head . . . (→here)