What body fat percentage is needed for flat abs?

I am apparently around 22.5% body fat, in the healthy range, but there is still a stubborn layer of fat around my lower abs. What body fat percentage should I be aiming for to shed it and get visible abs?

What is a VPN?

VPN is (Virtual Private Network) were first used by companies to enable their employees to securely access internal systems such as email remotely (e.g. from home or while on business trips). Today they are increasingly being used for personal use by individuals to protect their privacy while online in public places (e.g. when using the wi-fi connection in a cafe) or in a country where the internet is censored / blocked (e.g. China, Saudi Arabia…).