1) Used to observe whether the pipeline of fueling machine is filled with liquid, and its hose can be turned but sight glass cannot.
2) Materials:
a) Metal part: brass H62
b) Seal component: NBR
c) Sight-pipe: quartz glass (H and I are polycarbonate)
3) Performance: pressure resistance 0.3MPa
4) Surface treatment: decorative chromeplating.
5) Swivel sight glass can be connected directly with the hose by   users, omitting mid connecting device and reducing costs.
6) Can be rotated within 360o rolling bead inside can reduce the friction force while rotating so as to avoid the kink of hose, reduces wear and tear and keeps off the forming of tension.
7) Using life of hose is prolonged.
8) Ideal component for the oiling machine of stilt oiling type.
9) Types H and I combined with oil nozzle have dual function, i.e. substitutes of oil nozzle connector and serve for sight oil indicator as well.
10) Both quartz glass and polycarbonate are ideal window sight materials with good resistance to oil and low temperature and high transparence.
11) Remarks: generally outer-hoop for hose joint is not supplied for delivery.