This style of lamp is very common on ebay. It's been around for a while, so I thought I'd get a couple of the latest versions and see if they've changed much since I bought the last ones.
They haven't. It's just a very standard bit of circuitry with the only difference being that some random ones have an electrolytic smoothing capacitor in them.
The circuitry is very hackable. It's relatively easy to get the front cover off for access to the circuit boards, and the main current limiting capacitor can be changed to make the lamps run at a lower output for low level night or ambient lighting with a much higher life expectancy for the under-run LEDs. The PCBs also have the space for adding a smoothing capacitor and its discharge resistor if desired.
The LED panels use a very standard arrangement of seven 5050 LEDs with three chips in each wired in series to give a total number of 21 chips. These are run in the region of 20mA giving a lamp dissipation power of just over 1 watt.
These are a very standard and actually quite useful little lamp.