THE 495770 DIAPHRAM IS ON THE LEFT AND THE 495770 GASKET IS ON THE RIGHT. BOTH PARTS ARE CONTAINED IN THE KIT 495770. Neither part is available alone THE 495770 IS A GENUINE BRIGGS AND STRATTON PART. DO NOT BE FOOLED BY AFTER MARKET REPLACEMENTS, YOU WILL FIND THEY ARE NOT GENUINE BUY ONLY GENUINE BRIGGS DIAPHRAM 495770, (REPLACED BY GENUINE BRIGGS PART NUMBER 795083) THE AFTERMARKET REPLACEMENTS ARE NOT MADE LIKE THIS ONE IS. THERE IS A DIFFERENCE AND IT IS AN IMPORTANT DIFFERENCE. This 495770 diaphram and gasket set is probably the one item that can go bad on a classic 3.0 thru 4.5 horsepower briggs and stratton engine, more so than any other repair item. If your engine is surging or simply running rough, it is safe to say that you should strongly consider changing out the 495770 diaphram and gasket. Do not try to reuse this diaphram or gasket. The 495770 kit is so cheap why REMOVE IT AND INSTALL IT AGAIN, just to find out you should have replaced it. If water has entered your fuel tank, then water is now in and around this diaphram. The water will cause the engine to run rough and there is not an easy way to remove the water without removing the 495770 diaphram and gasket. The Briggs and Stratton 495770 diaphram works with the metal fuel tank and if installed wrong, it will cause problems. The diaphram must go on top of the fuel tank then the gasket on top of the diaphram. A dirty air filter can cause problems with the 495770 diaphram. If you have recently had a real bad clogged air filter, and your engine is still running rough, you should change out the 495770 diaphram and gasket. Next time, don't let your air filter get so dirty. If the above did happen to your engine, the next part to fail is the spark plug. The dirty air filter caused your engine to run rich and now the spark plug is fouling and will need to be replaced. See our spark plugs for your engine, you will probably need a J19LM OR RJ19LM, BOTH ARE THE SAME, THE ONE BEGINING WITH AN "R" HAS A RESISTOR FOR RADIO NOISE REDUCTION. SPARK PLUGS