This is an ACOG TA33-8 Advanced Combat Optical Gunsight (3x30 .223 BDC with TA60 mount). It has dual illumination; fiber-optic for daytime use and tritium-illumination for low light use using a chevron aiming point. The chevron is yellow in high lighting conditions and red in lower light. This sight system has a .223 bullet drop compensator (BDC). Aerospace seals make the ACOG waterproof to Navy Seal Depths. This item is $841.00 plus $10.00 shipping and handling.