Briefcases are box-shaped bags that have handles (may have on one side or two) and may have shoulder straps. Briefcases are most often known for their use by professionals to carry important documents. Briefcases may also be designed to carry laptop computers.
About Zipper:
A zipper, sometimes called a 'slide fastener' is a device consisting of two toothed tracks or spiral metal or plastic coils, each bordering one of two edges to be joined, and a piece that either interlocks or separates them when pulled.
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