Tools like the 121955 are "deep" or "long" (100mm) to reach recessed bolts.

Ideal for heavy-duty automotive applications where a standard-length bit cannot reach the fastener.

Components for fencing or mailboxes, such as the Architectural Mailboxes In-Ground Post , which require "deep" setting in concrete for stability. Product Details: Ombra 121955 Bit Socket

This specific tool is widely available from automotive and tool retailers:

Available at stores such as Yandex Market and Ozon .

The phrase "" does not appear to be a standard technical name for this tool. However, in the context of hardware and construction, it often describes:

1/2" drive, Torx T55 profile, 100mm total length.