Iron On T-shirt Transfers?

Can you use white t-shirt transfers on gray shirts or do you have to use the dark ones? I know this is probably a silly question but gray is still light enough. I just thought I would ask. Thanks ladies

I'd say that if your image has a lot of white or light colors on it, to use a dark transfer... but if it has dark blues, black, or purple, I'd just use a white one.

I've had good luck with the regular transfer on gray shirts. Keep in mind on the "dark" transfer that you are going to have WHITE on the shirt unless you totally cover the transfer with color/patterns.