Thank you for your valuable feedback!
We truly appreciate your input. Indeed, for users who need a more permanent connection—especially for hard-to-access batteries—the CTEK Eyelet M8 accessory is often the ideal solution.
However, the Eyelet M8 is currently only compatible with certain models like the CTEK Lithium UK Set or MXS 10.0, which are more specialized for either lithium or lead-acid batteries exclusively.
The unit you purchased, the CTEK CS One, is a versatile charger designed primarily for workshop or multi-vehicle users who switch between lithium and lead-acid batteries. Due to its unique adaptive polarity and smart connection design, it does not support bolt-on accessories like the Eyelet M8.
If a fixed connection is a key priority for you, we recommend considering a charger dedicated to one battery type, such as the MXS 10.0 (for lead-acid) or the Lithium XS UK Set (for lithium). These support the Eyelet M8 for easier long-term setup.
We’re here to help if you’d like guidance on the right setup based on your battery type and usage. Thanks again for choosing CTEK!
Regards,
Forexengineer