One of the interesting new products that was on display at the Taiwan MOA Exhibition 2022 is the Hummingbird Bolt Carrier from Maple Leaf. Designed for use in GHK-spec'ed M4 gas blowbacks, it can be easily installed without the need to make modifications --- just remove the GHK bolt carrier and chuck in the Maple Leaf Hummingbird and you're ready to go. It increases the cyclic rate of fire which can be up to about 18 rounds per second depending on certain factors such as barrel length and BB weght. It is compatible with old and new GHK AR GBB tech.