A hook is some easy way to extend or replace a certain part of the source by your own methods. They are often used for providing pre- and post-processing userfunctions in the core as well as giving control totally to a method provided by some extension author. 
The big advantage of using a hook instead of the older X-Class mechanism is the ability to enable more than one extension to extend the same class or method. This has been discussed in the developer mailinglist for some time and is also explained in the TYPO3 Core APIs document. 
The drawback is, that a hook has to exist before you can use it. So if you are in a situation in which you would like to extend a core or extension's functionality, just ask the source's author to provide a hook for you in the next release.


1. How do we control quality?
a) Pay attention to adaptation for manufacture process 
b) Approval report for shipment 
c) Third party inspection is accepted
d) Keeping quality guarantee for a long period
e) Guaranteeing quality inspection of each product before assembly and packing.
f) Comply with ISO 9001
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We are a factory manufacturing .Our products mainly consist of: forged riggings, hoisting pulley block, clevis hooks, eye hooks, safety hooks, swivel hooks, shackles and so on. With the passed 10 years of hard work and pursuit of better quality.
3. What are our advantages over others?
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d) Any request from the clients would be treated carefully by our experienced staff, the quality of any order would be highly controlled by our skilled engineers.
e)   QINGDAO SINCERE METAL PRODUCTS COMPANY teams would like to welcome clients from home and abroad to work for the win-win situation and reach our target: Making Business More Fun!
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