These are the correct connecting links for SRAM's 12-speed Eagle chains. They are great for installing new chains and fixing chains on the road and trail, too. They come in a four pack, for use with four chains.

Disc brake mount adaptor. - Includes stainless steel adaptor and caliper bolts

SRAM PressFit 30/English Bottom Bracket Adaptor allows conventional threaded bottom brackets to be installed in a PF30 frame. - Not to be used with internal threaded bottom brackets; compatible with BBs that use two external cups