The unique shackle design hinges and rotates to allow leaf springs to flex and compress without additional spring stress. TeraFlex Revolver Shackles are self-supporting and fold against themselves on level ground.

Because the shackles are a bolt-on kit, they can be installed easily with aftermarket suspension systems.

The Revolver shackles were originally built by Metal Made Rite. In 2000, Metal Made Rite teamed up with Tera Manufacturing, Inc. which significantly reduced the cost to manufacture the shackles and allowed Tera to pass the savings on to the consumer.  At the time this article was written they were just less than $200 USD for a pair. 

While TeraFlex does not advertise it, the Jeep 'FJ-40 Revolver Shackle (Part# RFJ-40)' will work on a Daihatsu Rocky / Daihatsu Feroza / Daihatsu Sportrak.  As they provide the 3" gap required for the body mount and stock leaf spring mount.

RJF-40 Installation Guide

When installing TeraFlex Revolver Shackles on a Daihatsu Rocky / Daihatsu Feroza / Daihatsu Sportrak you may need to do the following:

1. Jack up the car so the back tires no longer touch the ground.
2. Start with the passenger side, it is easier, the driver's side has a muffler in the way.
3. Using 17 mm wrenches loosen the nuts on the existing shackle.  I had to resort to using an impact air gun and penetrating fluid because of the bolts.  To get the the upper bolt I removed the plastic fuel tank covering (12 mm bolts)
4. Knock the old shackles out with a hammer, again this will be easier if the tire is not touching the ground which means the leaf spring is totally relaxed.
5. The body mount has two rubber pieces that have lips on them.  In order for these 3" shackles to fit you will need to cut the lips off, I did it with a hack saw and a bench vice.
6. Also the metal bolt sleeve that is part of the stock leaf springs is too long as well.  Using an angle grinder, cut down this sleeve so that it is the same length as the metal sleeve that comes with the revolver shackles.  I had to do this on the vehicle.
7. Re-insert the rubber pieces into the body mount and insert the metal sleeve that came with the revolver shackles.  Insert the other metal sleeve into the the leaf mount you cut down too, it should slide right in.  So they don't rust together, use some grease.
8. Put the revolver shackles in place and slide the new bolts/washers through. and tighten the nuts (19 mm bolts and lock nuts).
9. Do the same on the drivers side, except you now have the muffler to deal with.  I decided not to deal with the exhaust system and just cut the old shackle off (through the bolts) with an angle grinder.  If you do this be careful not to damage the rubber pieces or the rest of the car/leaf springs.
10. Repeat steps 3-8 and lower the car.
11. When i put it back down my muffler was touching the revolver shackles, so I used some wire to hold it back.