We have different definitions of the surface gravity (SG) of a horizon since we can say we have distinct classifications of horizons. The SG has an underlying role in the laws of black hole (BH) thermodynamics. being constant in the event horizon. The SG also acts in the emission of Hawking radiation being connected to its temperature. https://poolsproductscanadas.shop/product-category/hayward-sp0704-valve-parts/