Patent ID: 7357453

Claim:
A chair comprising a seat; a backrest; a first armrest; a second armrest; a seat support structure; means for supporting the lower back of a seated person; a first slider; a second slider; a first slideway having a plurality of cavities; and a second slideway having a plurality of cavities; wherein, said means for supporting the lower back of a seated person is spaced from said backrest and said seat; said first slider and said second slider are disposed at two opposite ends of said means for supporting the lower back of a seated person; said first slideway is cooperating with said first slider and is connected to said first armrest; said second slideway is cooperating with said second slider and is connected to said second armrest; said first slider and said second slider comprise each a block capable of sliding along said slideways, a pair of protrusions is disposed at two opposite sides of said block, and a through hole and a fixing hole are oppositely formed in said block between said protrusions.