Screenshot by Lance Whitney/CNET

Third-party versions of the new Lightning-to-30-pin adapter cooked up by Apple are now selling via Amazon and eBay.

Amazon shows generic versions being sold through two companies -- Nanotch and iTronz. Nanotch is offering the 7-inch cable adapter for $17.95, a part that Apple sells for $39. iTronz is selling the smaller stub adapter for $9.99, for which Apple charges $29.

Both items are available for preorder, with the cable adapter scheduled to be released September 30 and the stub adapter September 26. Nanotch has a 94 percent positive review on Amazon, while iTronz has scored a thumbs-up from 96 percent of buyers.

Vendors have also cropped up on eBay hawking generic versions of the stub adapter for $11.99 and higher and the cable adapter for $14.99 and higher.

So are these cheaper third-party versions worth scooping up, or is it a case of buyer beware?

CNET contacted Apple and Nanotch for comment and will update the story if we receive more information.

One eBay vendor said the generic adapter would work with the new iPhone, while another said the main difference is that it's not made by Apple.

But since the 30-pin adapter is a brand-new product, caution is advised. You should certainly wait until you actually have the new iPhone, iPod Touch, or iPod Nano before ordering a generic adapter, so that you can quickly and easily test compatibility. And if you don't go the Apple route, be sure to order from a vendor that offers a money-back guarantee.

The Lightning-to-30-pin adapter lets buyers of the new iDevices connect to their existing accessories and components. But the adapter does not offer video out, leading to reports that Apple will sell VGA and HDMI adapters in the coming months. Apple's order page lists the 30-pin adapter as shipping in October but with no specific date listed.

(Via 9to5Mac.)

Update, 9:15 a.m. PT: Adds responses from eBay vendors.