Please tell me the name of the two black cables st 15

In step 15 there are 2 black cables can anyone tell me where i can buy one or two.

thank you!

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 0
crwdns2934285:0crwdne2934285:0