Marshall boxes of entrance socket MR-V13, original of entrance sockets funnels, box connection serves as sunk connection field for mono. Four-hole drilling, outside diameter 95mm, hole diameter approx. 60mm, depth 50mm, supply without socket
This is an original Marshall replacement part, and I would say it's a good feature with any speaker cab that uses 1/4" jacks. The recess protects the plug from any accidental force, and the plastic is nice and thick. That as it may it still comes for the price of a Marshall part and I'd like to think it's pricier than its actual value. Even so I would repurchase in a heartbeat.