Made in the UK. Police Approved: Secured by Design.

Key Shields

A Faraday Bag designed to protect Car Key Fobs from Relay devices, thus preventing 'relay theft'.
Prevent theft of your vehicle by 'relay theft', by using the Key Shield Faraday Bag.
A discrete Faraday Bag, (unbranded) for Car Key Fobs. Prevents 'relay theft'.

All about Faraday Bags?