Use the original orange cap for Berryman 5 gallon carburetor cleaners. Gallon can of Berryman B9 carburetor cleaner. When I received the jar with the original orange lid, I could turn it upside down and it wouldn't leak. I examined the orange cap and black cap that came with the mounting strap. The seals on the Berryman cap were black material that was definitely designed for carb cleaner, while the cap that came with the tape has an off-white seal. I compared the edges of the two lids and they appeared to be the same, except for the orange Berryman lid which had steel locking tabs. Using airplane scissors, I cut the metal tabs flush with the bottom of the slots in between. I sanded down the raw edges and hammered them down so they don't stick out. The closure strap held the modified original orange cover perfectly. The entire conversion took about twenty minutes. I now know that having a smaller machine attack the seal on a thinner black cap will NOT degrade the seal.