This bistable relay module provides a compact, onebutton startstop solution for car modification projects. It uses a latch (bistable) relay to hold its output state after a press, so power remains on or off until the next button action. The module supports 5V and 12V systems and is listed here as the 5V variant (Color : 5V). Key benefits Onebutton startstop control: press once to start, press again to stop, with a single, simple user action. Selflocking (bistable) operation: the relay maintains its state without continuous power, reducing electrical load and wiring complexity. Easy integration for car modifications: designed to work with typical automotive control circuits and custom installations. Compact, singlemodule solution: a small footprint suitable for dashboard or engine bay mounting in DIY projects. Reliable, purposebuilt for automotive use: provides a straightforward means to implement a startstop function in custom builds. Key attributes Functionality: bistable (latching) singlebutton relay module enabling startstop control and selflocking behavior. Compatibility: designed for 5V and 12V systems; this listing specifies the 5V variant (Color : 5V). Size/Form factor: compact module intended for easy installation in vehicle projects and other electronic assemblies. Material/Construction: standard electronics module (PCBbased) suitable for integration with common automotive wiring. Performance: fast state change with latching output; maintains state without continuous current draw. Two to three use cases Case 1: Add a onebutton startstop feature to a custom vehicle. or augment a conventional ignition setup with a pushbutton control that latchets on start and remains engaged until the next press. Case 2: Interface a secondary power circuit with a latched on/off control. Use the module to power auxiliary devices (lights, pumps, or electronics) after a single press, with the state retained without continuous power. Case 3: DIY automotive prototype or test rig. Use the bistable relay to simulate ignition states in development projects, allowing quick switching between on and off without constant power consumption. Notes Proper wiring and safety practices are essential when integrating into vehicle electrical systems. Verify compatibility with your vehicle's ignition, accessory circuits, and any relevant regulations. This listing corresponds to the 5V variant (Color : 5V). If you require the 12V version, please check the product options or contact support for availability. This description preserves the original product's brand, specifications, model, and features while presenting clear, customerfriendly information intended to improve readability and support informed decisions.