They have an on/off switch on the bottom. When the lid is turned on, the light is off while the solar lid soaks up sun during the day, and then the lights turn on automatically at night. To test the light, put your hand over the entire top to simulate darkness and you should see the LEDs turn on.
They come with a rechargeable AAA battery that is easily replaceable.
The lids are two piece, with a rust resistant 304 grade stainless steel band that twists over the plastic solar insert. Solar lights sold elsewhere don’t include the band or come with a tin band that rusts.