This lens caps is specially made for covering the eyepieces of binoculars, such as 10x50 or 12x50 binoculars.
Internal Dimensions: 115mm (L) x 42mm (W)
Note: the size is measured as internal diameter of the cap, which is equivalent to the external diameter of the binocular lens including the lens housing (eyecups).
Depth: 18mm
Material: rubber.
Note: This listing is for ONE large lens cap which can cover both eyepieces of binoculars (as shown in the picture). The cap is made of rubber material which is flexible. For this feature, the cap can normally accommodate lenses with slightly bigger diameters. For example. this cap can cover binocular eyepieces (including the rubber eyecups) with external diameter around 42-45mm.


Note: this image is for illustration purpose only. This particular lens cap is made for covering binocular eyepieces, not for the objective lenses
Note: The size of the lens cap is measured as Internal Diameter of the cap, which is equivalent to the external diameter of the lens including lens housing (as shown in the picture above). Please allow a small difference in measurement (eg. 0.5-1mm). A rubber cap can normally fit a slightly bigger lens than the specified size (eg. +1mm to 2mm depending on actual size).
If a cap is slightly bigger than the external diameter of the lens housing and there is no matched cap size available for the lens, you may consider putting an adhesive cloth tape around the internal edge/rim of the cap. This can often secure the cap on the lens.