Material: L-BAL35 glass
Usage : used for the focusing of blue & blue-purple laser
Focal Length : F=4mm
Surface Treatment: coated
Do not touch the lenses and its surface with your hand directly,
and do not let the lens surface touch hard object directly , so as
not to scratch the surface. Usually we pick it up by using a
plastic tweezers, if the lens is dirty due to our careless, the
most simple and effective method is washed with water directly, and
then wipe off lightly with hemp cloth.
P.S. this item is a special product, we'll make sure that the
product is new and work well before we ship out the goods, once
sold out can't be guaranteed and replaced.