What is the mosquito-repellent incense in the hotel toilet?

It's mosquito-repellent incense, but it smells of sandalwood.

Some sandalwood-flavored mosquito-repellent incense, very thin and particularly fragrant, are generally sold in stores.

My family runs a small shop. Generally, a box of mosquito-repellent incense in 2.5 yuan and a box in 4 yuan are not expensive, but most people don't buy that kind (in fact, it can kill mosquitoes, and I can't figure out why the sales volume is not good)