Sigma 52mm Lens Cap

The set arrived in a white box with a company logo on the centre, inside was 3 caps, elasticated leash and a cleaning cloth.

The leashes need to be attached to the caps by feeding through the small hole, and pulling through and looping to secure, you then fit the elasticated section round the front of your lens avoiding the focusing ring if possible, the pin that secures the loop to the string doesn't sit flat so you might have to press underneath.
It makes it much easier to keep an eye on...