Many many years ago when landlords needed to lockout a tenant in an attempt to collect overdue rent or to evict, they would use a CUP, SHOE or BOOT) which they placed over the door knob that prevented the tenant from using their key to enter.
I wish to locate one of these specific devices for personal security puposes. Can anyone assist me in identifying the name of this product and help me determine if they are still being manufactured and sold?