Chubb Manifoil Lock MK IV Combination Safe Locks NATO 20.42.172 Complete MK4. NATO Lock: 20.42.1726. The item "Chubb Manifoil Lock MKIV (Mark 4) Combination Safe Locks 2004 NATO 20.42.1726" is in sale since Thursday, April 29, 2021. This item is in the category "Collectables\Tools & Collectable Hardware\Collectable Locks". The seller is "eddies_vintage_store" and is located in Shoeburyness.This item can be shipped worldwide.