Water provision and distribution systems comprising faucet stream straightener with and without aeration, and spare parts and fittings therefore, included in this class; liquid flow regulators for water provision and distribution systems, namely, being components for sanitary fittings, faucets and shower heads; faucet aerators being components for sanitary fittings with or without aeration; faucet stream straightener with or without aeration namely components for sanitary faucets and shower heads, in particular, hand showers, adjustable shower heads, fixed head showers, as well as kitchen sink spray heads and spare parts and fittings for shower heads, included in this class