This patent is obvious-- it is a "living hinge," with the "unique" aspect that it is "with a laser." Such structures are routinely created in plastic mouldings-- hinges on boxes of baby wipes, strain relievers for wires, etc. This is an obvious extension of such plastic mouldings, but with a laser.
See "living hinges" at the bottom of this page:
That's a patent application, not a grant.
Usually a granted patent is identifiable on Google patents site:
the document's Publication type in the blue cartouche shows Grant as opposed to Application
the cartouche shows the corresponding Application Number on the following line
the Discuss this Application blue button reads Discuss this Patent instead
Am I in the clear to manufacture this product?
Not necessarily. Even if the marked patent is expired, there may be other patents (or designs) that are pending and in force, which would cover the product. The key way to assess this is to perform a freedom-to-operate search.
However, if you are intending to produce something which is identical to a product ...
A) That would be a legal opinion that would be best asked - in that form - to a patent attorney.
B) To answer the underlying question, of how do I find out whether a patent is expired?
There are several things to take into consideration - what patent term applies to the patent, whether there were extensions, whether the patent was allowed to lapse early (...