The Shield is an overstable putter from Westside. This disc is more stable than the Swan and a straighter flyer than the Westside Harp. It's a tallish disc at 2.5cm tall, and is relatively flat. Like all Westside putters, this disc is available in the BT plastic blends.
Originating out of FInland, Westside is now owned by Latitude 64 and Dynamic Discs. But they still continue to pump out a full lineup of discs.
While they are mainly known for their quality high speed drivers they still have discs suitable for, well, players like us including the popular Harp putt & approach disc.