A new and distinct cultivar of Poinsettia plant named \u2018PER1904\u2019, characterized by its uniform, upright and mounded plant habit; freely branching habit; recurved dark green-colored leaves; mid-season flowering response; inflorescences with pink-colored flower bracts that are recurved; and excellent post-production longevity. The gutter insert can be connected end-to-end to produce a modular gutter insert having a desired length for placement in a gutter or like device. Using the formulations according to the present invention, it is possible to suppress antagonistic interactions between different active compounds. A sensor secures to the rest and detects proximity of the user’s face to the rest.