I have attached two pictures with measurements and cast-in numbers, I need two mechanisms with the "40471" number and one with the "L31538A" number. Please let me know if you need more information

Methodology for determining left from right?

Tom from SWISCO

Jun 3, 2013 11:51 am

Good morning! Check out our 39-031 & 39-032 Truth EntryGard operators. These appear to match your originals quite closely, but you can review our specs to verify.

Dimensions for 39-031

4 Replies

Quick Learner from Wisconsin

Aug 3, 2020 6:52 pm

Hi Guys

Is the industry clear on handing terminology ?

I see conflicting views on the subject.

With your help I have identified the two different operators I need. Both numbers have a left and right mounting position. INSIDE the window looking out or OUTSIDE the window looking in ?

Thanks, Dave

Tom from SWISCO

Aug 6, 2020 11:15 am

Hi, Dave. This industry is anything but clear when it comes to the matter of left vs right. Every company defines it differently, and even the same company will change its mind over the years. You're better off ignoring the concepts of "left" and "right" entirely and base your decision on the design of the part in question. What side are the gears on? What side is the handle on? And the arms? Stuff like that. That's what I do and it saves me the headache.

Quick Learner from MI

May 29, 2026 1:15 pm

This helped me figure out which one I need. I have 39-031 and 39-032 at my house now and have been trying to deternine which one I need for three other windows. You have to take the handle off (remove the set screw) and then pop off the cap to see where the gears oare.
I'm looking at my at the gears and handles...
Facing from the inside, looking outside...
My window with the crank handle on the right of the gears, cranks out to the right.
My window with the crank handle on the left of the gears, cranks to the out left.
From that and their pictures you can figure out that 39-031 cranks right, so 39-032 will crank left. That's what's the case with the ones I've been installing.
I can't speak for other models #'s ... but if you look at your window and can determine where the handle is and where the gears are you should be able to match it to their pictures and determine what is right and what is left. You don't have to uncover more than that to figure it out.