The main part of the ball valve is ball which has a hole in middle. When that ball rotate 90 degree it close or open. They are useful for applications which have to be rapid.

Advantages;
Minimal loss of pressure
Easy to opening and closing
Good leak tightness
Compact design

They are designed for natural gas plumbing and they are according to TSE

Material Structure:

Body: MS58 brass
Ball: Nickel coated brass

Connection:
Screwed

Nominal Diameter:
DN15 (1/2”) - DN50 (2”)

Working Pressure:
Up to 16 bars

Temperature Ratings:
-40ºC to 110ºC

Typical Applications:
LNG and LPG lines
Fuel-oil lines