The B-grade LED bars are all fully functional items. B-grade goods may include ex-display products, returns or LED bars that have not passed our final quality inspection and have defects on the silicone seal. Therefore ALL B-grade LED bars are expressly sold as non-watertight! (The water cooling parts of PRO² bars are watertight!) The functionality of these LED bars is not adversely affected if they are protected from moisture and high humidity during use.
Technical data and description, see here!