This medium ORIGINAL Bristol Spline Wrench set SS-408, is our medium size set
for working on Collins, Hallicrafters, and aviation Radio Gear, and other
electronic gear that uses the Bristol Spline set screws.
HOW TO READ OUR PART NUMBERS: On the "L-Keys", the first letter is "S" for all
spline L keys. The next three digits indicate wrench diameter in thousandths of
an inch, ranging from the tiny .033 to the hefty .454! The next digit indicates
the number of "flutes" or engaging points for the wrench...either 4 or 6
flutes.SS-408 10 short arm keys: S-060-6, S-069-4, S-072-6, S-076-4, S-096-6,
S-111-6, S-133-6, S-145-6, S-168-6, S-183-6
We also offer a smaller set (SS-508) in another listing.