I bought these probably in the knowledge that as I was getting 10 lights for 20 pounds that they were not likely to be anything special, but would merely provide ambient light in the evenings. I had not actually realised that they are classed as 'path lights', to illuminate your way, I suppose indicating that they will not attract passing aircraft, but provide sufficient light to stop you falling into the flower beds when finding your way home on a Saturday night.
I actually broke two putting them into the ground, my own fault really for being a little heavy handed, so please don't make the same mistake. I would suggest that you use a tent peg or similar item to test the ground before placing the lights.
Having said that the remaining lights work perfectly and provide a nice 'star' like light effect along the length of the garden.
Cheap product which for me a least worked well.