Doing any type of heavy timber work and having a good solid connection between pieces is vital to the longevity of any project, particularly when final project is expected to be outside and exposed to the elements, think garden trellis, pergola, deck or anything else you might be considering. Found these from Ct Post And Beam, called T-Rex connectors, not to be confused with Trex. Yep, so that metal sliver on the base and vertically in the middle is the connector, pretty cool, looks nice and clean, good design.
