Scarabs of this type, with generalised hieroglyphs and geometric patterns, were popular during the Middle Kingdom. They gain popularity during late Dynasty 12 to Dynasty 13, circa 1850–1640 BC. The hieroglyphs do not translate into a specific phrase but were chosen for their popularity and general apotropaic values.
To find out more about Ancient Egyptian amulets please see our relevant blog post: Egyptian Amulets and their Meanings.