Scott,

here it is below

4031 High precision 1.75" x .742" x 2.14" 1.6 ounces 61.2 oz-in .25 sec/60º
Dual BB Nylon Gears Coreless 30 and 60 sized helis, pattern aircraft

This servo was replaced with the 4131 that was 90oz-in and speed was faster to 0.23sec and then the 8101 where they improved the bearing spacing. The 8101 is probably the best precision non-digital servo on the market. They are bullet proof. I think you can still get 4131's and I know the 8101 is the latest and greatest in terms of non-digital precision servos. Basically the 8231 digital is a Digital version of the 8101. These 3 servos (4031, 4131, 8101) are extremely precise and smooth. I used to run the 4131's on everything except the rudder (4721) back in those days...early to mid 90's


All were really good servos. For the day the 4031 was on top of the pile as far as pattern servos go. But today there are better choices and digitals are such a huge improvement.

Troy