I got my first snakes 2 weeks ago and i have been feeding them 2 adult mice each. I want to get them on rats as soon as possible. I've been looking online at purchasing frozen rats but im not sure what size of rat to get. My snakes are all yearlings and are around 235-245g. They are around 1 1/2" in diameter, what rat is around that size? Weanling, small or medium?

Thanks for your help in advance.