Nema L5-20P TO NEMA 5-15/20R This Monoprice heavy-duty plug Adapter transforms a NEMA 5-15P or 5-20P straight-blade plug into a locking L5-20P plug. Buy with confidence: with Monoprice Lifetime Warranty on all cables, you can rest assured we stand behind our products and our customers Quality at a fair price: Monoprice rugged design and rigid quality control standards deliver high quality products at fair prices. Service & Support: you're never on your own with Monoprice products! We have a full team of friendly and knowledgeable technicians available to answer your questions