The Rail shims for 556 and 606 blades have dimensions 4 x 22 x 1mm. I have never been able to find a Synergy part number for them. Not to worry. The
Radix spacers for 600mm blades have the same 4 x 22 x 1mm dimension. Ron only has 7 in stock. I am not able to find them in stock anywhere else. I assume that's because Curtis stopped making/distributing blades. Once Ron runs out of these shims, your other option is to
purchase directly from Curtis.
BTW, I don't like the stock Synergy tail blade spacers. The outer diameter is only 9mm for the
106-804 and 10mm for the 305-312. The OD is too small for the blade grips. These Synergy spacers sit inside the curved aspect of the Synergy blade grips, so they can damage the blade grips other time.
These are other spacers I tested. Their OD are larger than the stock Synergy spacers, so they overlap the tail blade grips.
The synergy blade grips need about 2.8mm worth of spacers for the Synergy tail blades. I am not able to find 1.4mm thick spacers. I am using a combination of
white POM EDN-1159 and either the
Compass 10-5006 nylon spacers (which I prefer) or the
SAB H0078-S metal spacers.
This is my E7SE tail. I'm using the white POM EDN-1159 and SAB H0078-S spacers on it. The SAB spacers are only 12mm OD, so they barely clear the blade grips.