the lens covers protect both the objective and ocularlenses of the scope. They willkeep your lenses clean when not hunting.

SIZE                                      O.D.  RANGE
ALC1	1"	-1	1/16"	25.5mm-27mm
ALC2	11/32"	-1	12/32"	34mm-35.5mm
ALC3	17/32"	-1	9/16"	38.8mm-40.5mm
ALC4	5/8"	-1	12/32"	41.9mm-43.4mm
ALC5	3/4"	-1	13/16"	44.6mm-46.1mm
ALC6	27/32"	-1	29/32"	46.8mm-48.3mm
ALC7	3/32"	-2	3/16"	53.5mm-55mm
ALC8	1/4"	-2	5/16"	57mm-59mm
ALC9	7/16"	-2	1/2"	62mm-63.5mm
ALC10	19/32"	-2	21/32"	66mm-67.5mm