What substance is commonly applied to the handles of forcible entry tools to protect them?

Linseed oil is commonly applied to the handles of forcible entry tools to provide protection and enhance durability. This natural oil acts as a wood preservative, helping to prevent moisture absorption and decay while also promoting a smoother finish that is less prone to damage. The application of linseed oil can be important in maintaining the integrity and effectiveness of the tools, especially in environments where they may be exposed to harsh conditions or heavy usage.

While varnish, wax, and base coat paint might also offer protective qualities, they do not have the same wood-preserving properties that linseed oil provides. Varnish can create a harder finish but may not be suitable for tools that require a non-slip grip. Wax can offer temporary protection but tends to wear off quickly, while base coat paint could alter the tool's grip and functionality over time. Hence, linseed oil is the preferred choice for maintaining the handles of forcible entry tools.