Bip39 bits https://list.ly/abregeouoh While it utilizes BIP32 method it is possible to nevertheless import BIP39 seeds into Electrum wallet. Also besides BIp32 there is BIP44 Variation which some wallet use for your technology of seeds. For words that only have 3 letters, there is absolutely no 4th letter. For instance https://45listing.com/story22509852/bip39-to-binary-the-single-best-strategy-to-use-for-bip39-recovery-tool-https-x-com-tundra838554