Flow Sight with Nylon Ball Inline Double Window 1/4 In.-18 NPT Hex Dia Flats (In.) 7/8 in Max Working Pressure (PSI) 435 psi Max Operating Temp 180 Degrees F Sight Length (In.) 1 1/16 in Sight Dia (In.) - Overall Length 3 9/16 in Aid in Viewing of Dark Fluids in Dim Light Conditions Condition or Clarity Vertical or Horizontal Fluid Lines to Observe Fluid Flow Features Buna N Seals and Borosilicate Sight Window Female x Female NPT Solid Brass Bar Stock Construction