40p to 26p Downgrade GPIO Ribbon Cable for Raspberry Pi 3 / Zero 1.3 / 2 / B+ / A+ (8" 20cm) *** 40p to 26p Downgrade Cable ***, Adapts 40-pin layout to a 26-pin layout (40p to 26p, Not 40p to 40p) Compatible with Raspberry Pi Model 3B/Zero1.3/2B/B+/A+ GPIO Use your model 3B/Zero1.3/2B/B+/A+ with older prototypes consisting of a 26-pin breakout 8"(20cm) cable length Pin #1 is marked with a red stripe