Use the 1-Stage Clamp-On 138mm Round Zip Box (80-85mm) from Wooden Camera to attach one filter to the front of your lens. The Zip Box clamps onto lenses with an external front diameter of up to 3.1-3.3". No need to worry about sandwiching a diopter into a standard matte box tray, this round sunshade/filter holder's tray-less design will fit a diopter of any thickness. The Zip Box's lightweight yet strong design features a unibody rubber shade with stainless steel components. The sunshade's wide design prevents vignetting even when using wide lenses and large camera sensors.