Brief:
RMS Motor Adapter for Large Motors (54mm to 75mm).

Construction:
The motor adapters come with three components machined from 6061-T6 aluminum. The first is a centering ring which fits around the motor tube and is tightened or loosened by a stainless steel hex head screw. The second is an adapter ring that fits around the aft end of the motor tube just above the motor's aft closure ring. The third is a spacer to ensure the motor's nozzle is centered properly in your retainer. To use the motor adapter, you must have an Aero Pack on your rocket. These components are also Type II black anodized to be both wear and corrosion resistant. They come in three sizes - the A5475 (54mm to 75mm @ $37), the A6475 (64mm to 75mm @ $39) and the A7598 (75mm to 98mm @ $45)

The Large Quick-Change Motor Adapter differs significantly enough from its smaller cousin, the Quick-Change Motor Retainer, I felt it required its own review. Like its smaller cousin, the adapter allows you to use a smaller-in-diameter motor casing inside a larger-in-diameter motor mount tube in conjunction with Aero Pack's Quick-Change Motor Retainer system. So you can use a 54mm motor in a 75mm motor mount tube, a 64mm RATTworks hybrid motor in a 75mm motor mount tube, or a 75mm motor in a 98mm motor mount tube, depending on the size of your Large Quick-Change Motor Adapter. However, rather than being a two piece component consisting of an adapter tube and a spacer like the A2938 or A3854, the large adapters come in three ring-like pieces.

After placing an order for the adapter on the Aero Pack website, you'll receive the product in a priority mail box. When you open the box, you'll find the adapter components in a zip-lock plastic bag. First, after you've built your motor, you'll need to find the adapter ring. It's the one which slides over your motor casing and does not have the hex screw in it. Simply slide the adapter ring over the top of your motor casing down snugly against your aft closure ring. Now take the centering ring with the hex screw and slide it onto your motor tube from the top until it is located approximately three to four inches below your forward closure. Lock it in place by using the proper sized hex key to tighten the centering ring onto your motor tube. Now place the adapted motor into your motor mount tube and place the spacer into your retainer cap. Then tighten the retainer cap onto the retainer and you'll find that the motor is retained securely without any friction fitting and won't slide either forward or backward.

Construction is exemplary and the product works like a charm. I've used the adapters with both Aero Pack retainers and Giant Leap Slimline retainers and they work fine. Please note, though, that I have only used the Large Quick-Change Motor Adapter with AeroTech and Cesaroni motor casings. I cannot vouch for whether they work with Loki or AMW hardware. However, for the vast majority of commercial motors we use, the Large Quick-Change Motor Adapter is a godsend and an indispensable piece of hardware for big rocket rocketeers.

Finishing:
The units are flat black and hold up well to use in the field.

Overall Rating: 5 out of 5