樓頂大字分為特級做A爰片毛片免費69:發光字和(he)不(bu)(bu)發光兩種(zhong)。發光字(zi)(zi)(zi)(zi)分為吸塑字(zi)(zi)(zi)(zi)和(he)LED外(wai)露燈(deng)發光字(zi)(zi)(zi)(zi)，不(bu)(bu)發光字(zi)(zi)(zi)(zi)按材料分為鈦金字(zi)(zi)(zi)(zi)，不(bu)(bu)銹鋼(gang)字(zi)(zi)(zi)(zi)，烤漆(qi)字(zi)(zi)(zi)(zi)。樓(lou)頂(ding)(ding)大字(zi)(zi)(zi)(zi)即是(shi)由鋼(gang)結構支撐架(jia)和(he)金屬字(zi)(zi)(zi)(zi)形組成(cheng)(cheng)(cheng)的(de)大型(xing)(xing)廣告(gao)字(zi)(zi)(zi)(zi)。鋼(gang)架(jia)一般(ban)由(鍍鋅)角鐵焊(han)成(cheng)(cheng)(cheng)片梯或者方籠制成(cheng)(cheng)(cheng)，樓(lou)頂(ding)(ding)發光字(zi)(zi)(zi)(zi)字(zi)(zi)(zi)(zi)形由不(bu)(bu)銹鋼(gang)板或鍍鋅板做字(zi)(zi)(zi)(zi)殼(ke)，內(nei)置LED模組，吸塑字(zi)(zi)(zi)(zi)字(zi)(zi)(zi)(zi)面由亞(ya)克(ke)力板制作。LED外(wai)露燈(deng)發光大字(zi)(zi)(zi)(zi)則是(shi)在(zai)金屬板上沖好(hao)孔，然后再用激光切(qie)割(ge)成(cheng)(cheng)(cheng)型(xing)(xing)，.后焊(han)接成(cheng)(cheng)(cheng)字(zi)(zi)(zi)(zi)形，裝燈(deng)。固定在(zai)鋼(gang)架(jia)上完(wan)成(cheng)(cheng)(cheng)。