40201-ZY3-020ZB Case *NHB14M* - Overview. The 40201-ZY3-020ZB Case *NHB14M* is an essential OEM extension case designed specifically for Honda marine engine systems. Serving as a protective housing component, it plays a critical role in maintaining the integrity and reliable operation of Honda outboard engines. Crafted to meet exact factory specifications, this case assures seamless integration with existing parts, preserving system robustness and performance over time.. Key Features. Genuine OE