Top Entry Ball Valves

ball valves
(Ball Valve) A simple non-return valve consisting of a ball resting on a cylindrical seat within a liquid passageway.
A one-way valve that is opened and closed by pressure on a ball that fits into a cup-shaped opening
(ball valve) any valve that checks flow by the seating of a ball
(Ball valve) A ball valve is a valve with a spherical disc, the part of the valve which controls the flow through it. The sphere has a hole, or port, through the middle so that when the port is in line with both ends of the valve, flow will occur.

entry
introduction: the act of beginning something new; "they looked forward to the debut of their new product line"
An act of going or coming in
The right, means, or opportunity to enter a place or be a member of something
A place of entrance, such as a door or lobby
an item inserted in a written record
a written record of a commercial transaction

top
the upper part of anything; "the mower cuts off the tops of the grass"; "the title should be written at the top of the first page"
top(a): situated at the top or highest position; "the top shelf"
Exceed (an amount, level, or number); be more than
Be at the highest place or rank in (a list, poll, chart, or league)
exceed: be superior or better than some standard; "She exceeded our expectations"; "She topped her performance of last year"
Be taller than