The Abba S1 ground anchor is a decent bit of kit. It's the same one used by BikeTrac for their ground anchor. The Abba only comes with a red shackle but if you want different colour options, check out the BikeTrac version.

The S1 ground anchor features a wide internal aperture of approximately 42mm high × 75mm wide, which makes it compatible with the following Protector chain sizes:

• 11mm
• 13mm
• 16mm

It is just too small to accommodate our Protector 19mm chain and too small for our Protector 22mm chain.