The relays are Hella purchased from slantsixdan, he included the sockets. They are interlocking so that they can be ganged making for a nice tight installation.
The interlocking relay sockets are Hella, yes. The relays themselves? Hell no! I quit selling Hella relays in about 2005 when their quality abruptly skidded and I started getting a ridiculous number of failures. Switched to Bosch/Tyco relays and since that switch I can count the number of comebacks on one hand. Much better. The harness builder I use for custom-built/ready-to-install headlamp harnesses is associated with a Hella shop, so he was incorporating Hella relays...which are now made in China. Oooh, much better. Not! Fail-fail-fail. I've switched to having him build the harnesses minus relays so I can supply Bosch/Tyco units that actually stay alive.
