The 177-0933-003 is a stovepipe lens cap designed for use with the 177 series of watertight panel mount indicators. It features a 5/16-32NEF thread and incorporates an O-ring to ensure a water-tight, oil-tight, and dust-tight seal on the face of the panel. This high-impact plastic lens is part of an indicator assembly that accommodates a T-1 3/4 midget flange base lamp. These indicators are designed to meet or exceed the environmental and operational requirements of MIL-L-6723 and MIL-L-3661B, making them suitable for demanding applications requiring sealed indication.