Correct: newer models have no screw.

The whole reason I had to open mine up is that water got inside, and I don’t even use it in the shower. I think they removed the screw to either cut costs or make it more difficult to repair.

My previous one (an older model, which had a screw in the bottom) lasted a long time. This newer “sealed” one got water inside within 2-3 years and had no screw. Fortunately it seems that opening it up and cleaning the circuit board helped.