Inline flow sights can be used in either vertical or horizontal fluid lines to observe fluid flow, clarity or condition of medium. A ball float can be supplied to aid observation of flow of dark fluids or fluids in dimly lit conditions. Standard Features: 1/8, 1/4, 3/8, 1/2, 3/4 or 1 inch PTF connection Caution: Maximum working temperature up to 180°F (82°C) For applications requiring maximum working temperature over 180°F (82°C), please consult factory Caution: Scratched glass significantly reduces pressure rating.