That is the blue plug (center pin positive) and is completely compatible with all modern plugs of all the majors and there is no reason not to use them or any other brand if you like.

The only caution is if you plug a futaba servo with the modern J plug into your receiver you may have to save of one little tab and of there are some micro receivers that use Yup micro plugs and of course ya cant't use those without a hugh hassle.

Enjoy

John