If you were hoping to build a third-party band for Apple Watch, then you now have some resources about the official way to make that happen. Apple posted details about its ‘Made for Apple Watch’ program on its website this week, revealing technical specifications related to how to build lugs that meet its standards, as well as providing info about how it will supply lugs itself for accessory makers to use.

Apple never gave any indication it wouldn’t open up Apple Watch straps to third-party gadget makers, but this confirms the basics of how the program will work. As with Apple’s other “Made for” programs, however, including “Made for iPhone” (MFI), it will be making sure that after-market add-ons not of its own making match certain standards. MFI certification can be tricky to get, especially now that Apple supplies all Lightning connector components complete with embedded chips for use in MFI devices.

In this case, Apple is offering lug components to manufactures optionally, along with the option to build the parts themselves, using an extremely limited specific-use, non-transferable license. It’s likely Apple’s standards will be high when it comes to lugs created by third-parties versus those it’s supplying itself, but it’s unclear what the relative cost advantages or hindrances might be with either option.

The good news is that this will allow for accessory manufacturers to create a range of different types of bands, including those that incorporate the lugs into the strap itself, like the connector version found on the Apple Watch Sport Band and the Leather Link Band, or do something more traditional with the strap, as with the Classic Leather band.

It will probably take a while for the Made for Apple Watch program to spin up, so don’t expect to see officially sanctioned third-party bands hitting the market all that quickly. Many types of MFI-certified Lighting accessories rolled out slowly, but in that case there was likely more component complexity.