The nuts feature a self-locking design, so when they are fastened to a stud by hand, they will stop when they reach the "locking" portion. You will then need a wrench or socket to fasten it further, at which point it will "lock" in place.
Exhaust Studs Nuts Copper Gasket Kit For GY6 50cc 125cc 150cc
Alpha Rider 8pc Exhaust Studs & Nuts for 1984-2015 Harley Big Twin & 1986-2014 Sportster XL (Chrome, Zinc, #3/8-16, 0.375in)
YINETTECH 1 Set Exhaust Studs Nuts Gasket Kit Compatible with GY6 50cc 70cc 90cc 110cc 125cc 150cc QMB139 for Scooters ATVs Go Karts Moped Quad Engine
Yamaha XJR1300 1998-2003 Stainless Steel Exhaust Studs,nuts & gaskets.
Harley-Davidson all models 1984+ stainless steel exhaust studs & nuts x4 ES34
