Yamaha 2 stroke oil measure bottle (PN:OIL-MEASU-RE-01).
Never get confused again. This oil measurer has markings on the side for 25, 50 and 100 to 1 oil ratios. Just look at how much fuel you have added in your fuel tank and then fill the container with oil at your correct ratio up to the marking for that fuel quantity. Tip the oil in your fuel tank. It's that easy.