Dokushin Oji-san no Isekai Life: Kekkon Shimasen, Free na Dokushin Koso Saikou desu

Oda Gentoku, a handyman who runs a small “odd-jobs” shop in town, lived a carefree life while proudly declaring he would stay single forever. But one day, while working on an electrical repair job, he’s unexpectedly electrocuted and wakes up in another world! This is the story of a middle-aged man who remains steadfastly single, takes up his craftsman trade once again, and enjoys a free and easy life in another world.

(Source: Mangabox, translated)