Breakthrough X4 77mm ND Filter Review – Part One. There’s more to life than looks of course but it is difficult to avoid forming a first impression. From the moment I opened the box, this filter created two impressions. It looked like a high end piece of engineering and it stood apart from the crowd. Such an attention to detail by a manufacturer sends an instant message. ‘We know what we’re doing and we believe it is important to do it right’.