I recently bought this for replacing the upper pulley in a SRAM rear derailleur. It turns out that for SRAM the B pulley goes on up ( as guide pulley) and A pulley goes down (tension pulley). This info is on the diagram that is covered by a sticker in your video 0:40 . So I used the B pulley to go in the top side of the SRAM derailleur and the A pulley I put also on the top side of the Shimano derailleur of another bike I have here. I didn't use both on SRAM because the bottom pulley in the SRAM derailleur was still in excellent condition
Look to be an excellent replacement!
I recently bought this for replacing the upper pulley in a SRAM rear derailleur. It turns out that for SRAM the B pulley goes on up ( as guide pulley) and A pulley goes down (tension pulley). This info is on the diagram that is covered by a sticker in your video 0:40 . So I used the B pulley to go in the top side of the SRAM derailleur and the A pulley I put also on the top side of the Shimano derailleur of another bike I have here. I didn't use both on SRAM because the bottom pulley in the SRAM derailleur was still in excellent condition