The Huben Spare Parts for K1 · Diagram 6 · Filling Port brings together the essential components responsible for your K1's secure and efficient air refill system, giving owners direct access to the exact original parts needed to maintain, service, or restore this critical system — manufactured to the same exacting standards as the original air rifle, each part ensures a precise fit and reliable seal with every installation, helping preserve the K1's fill accuracy and preventing air loss while avoiding the wear-related issues that come from using generic or incompatible substitutes, so whether you're doing routine upkeep or a full restoration, your K1 keeps delivering the performance and reliability it was engineered for, shot after shot.