New.
                                                   Kit contains 47 electrolytic capacitors.
                                            All you need to recap  Marantz 3800 preamplifier.
                                               
                                                                      SHORT PREVIEW.

All electrolytic capacitors have limit of life.  Normally it,s  5 -8 years depends of quality.  Chemical oxidation, drying  and evaporation oil inside , location on the PCB board, type of signals  and voltages they working with  and drop value - that is major factors what is  destroying them. Capacitors extremely important to any audio device . Yon  can,t  build or create audio device on this planet  not using them. 
Non electrolytic capacitors will work  5 times longer   without change .

                                                                              INSTRUCTION.

Pay attention on each capacitor replacement procedure  what you are doing.  Remember - they all have " plus'  and " minus' polarity. Wrong installation will cause malfunction of your audio unit.  After changing  2 -4 capacitors in series always check  unit functionality.  It will help you not doing installation mistake. Pay attention on capacitor value printed on its body. After you remove capacitor  from PCB board mark plus side on PCB board.   It will help you not reverse plus  and minus when you going to install new one. Do not use old stock capacitors  even if they are new.  After 15- 20  years in stock  EVEN NEW  most of them will loose value and dielectric parameters . They will work but not long time.
  Remember   -   50% of your sound quality  -  directly from your capacitors value  and quality .
Axial capacitors polarity - on picture  #3.
Radial capacitors polarity - on picture  #4.

                                                               GOOD LUCK  AND HAVE A NICE DAY !