Find, attached to this message, a drawing of a screen knife latch for the picture window in our living room. I tried to take a picture of the latch, but our lousy camera cannot take close-ups. The manufacturer of the window is unknown, but "Entry-Gard" is stamped in the mechanism that opens the window. It looks very similar to a part listed on your site (Product Code 70-172), but the measurements are significantly different. Furthermore, unlike your part, note the dimple that is located in close proximity to the block-C cut-out.
Sincerely yours,
David S
