This is a Dynamite 500cc Fast Fill fuel bottle.  Leaky fuel bottles and costly spillage can dampen R/C fun. Dynamite's Fast Fill Fuel Bottle features a tight, leak-free lid and spout that allows for easier and cleaner refills. It also takes the guesswork out of how much fuel has been used. Molded-in measurement lines show how much fuel is in the bottle in increments as small as 10cc!