The G300 Series vented brass oil gage has a straight hex base with male pipe thread. A shield with machined viewing window surrounds the tubular glass sight. The viewing window has 360° adjustment for optimal orientation to view fluid after installation. The sealing gaskets are contained on both their ID and OD to facilitate trouble-free assembly after on-site repositioning of the viewing window. Standard Features: Gage base machined from brass hex bar stock Male tapered pipe thread base connection (1/8, 1/4 or 3/8 inch NPTF) .39 inch wide viewing window, length varies from 1.79 to 7.33 inches depending on gage selected 360° adjustment of viewing window Suitable for use with most machine lubricating oil Temperature Rating: Maximum operating temperature of 250°F (121°C) with standard Buna N seals. For applications not compatible with Buna N seal material, consult factory for available options and corresponding temperature ratings.