When did suspender clips become popular?

I've just been asked if someone costuming the play Night of the Iguana, set in 1940 should use clip or button suspenders. I *think* it's button, but I haven't been able to find any documentation (in a quick search) to back myself up. I do see that clips were invented in 1894.

I intend to look at the Sears catalog books from the 1930s and 1940s tonight, but I was wondering if anyone here knows when the change came?

I could not say as to the time they became popular but suspenders that are the button type are much better for actual use. The clip type has never worked for me, they always come off. Button type suspender pair well with dress pants and a lot of outdoorsman pants are made with suspender buttons already. For some suspenders go to the David Morgan web site and click on accessories.

http://www.davidmorgan.com/

Thank you! I pretty much figured that clip ons never became popular with people who wore suspenders every day, especially working people, as they would slip off.

Thanks!