CR39 bifocal lens 1.all index lens 2.progressive , flat top ,round top.single vision ,sunglass lens 3.semi finished lens CR39 bifocal lens We have all kinds of lens, All kinds of ... lens,flat top lens,round top, photochromic lens,Polarize lens,sunglass lens.And all kinds of RX lens.And all kinds of semi finished lens The following is 1.499/1.56 bifocal lens ...