Final answer:
Historically, soldiers were required to wear their uniforms while on leave so that MPs could monitor their conduct, and strict uniform regulations likely did not allow for exposed pens in pockets. While men had some leniency, deviations from the uniform code like exposed pens were probably not permitted.
Step-by-step explanation:
The question about whether exposed pens in pockets are allowed on which uniforms seems to pertain to military dress regulations. Historical contexts reveal that during times of leave, soldiers were required to wear their uniforms off-duty. This was primarily so that Military Police (MPs) could ensure military personnel adhered to prescribed behaviors, including uniform standards. There isn't a direct reference to whether exposed pens in pockets were specifically allowed or disallowed; however, it can be inferred that uniform regulations were strict and likely did not permit such casual deviations as carrying exposed pens, which could be deemed unprofessional or against the dress code.
It's also worth noting that while females in the military faced more rigorous scrutiny over their apparel and behavior, males experienced some leniency, although within limits. Non-compliance with dress codes, such as wearing unauthorized items or modifications to the uniform, would generally not be tolerated, suggesting that exposed pens in uniform pockets were likely not condoned. Locker clubs emerged as a reaction to such regulations, offering soldiers the means to discreetly change into civilian attire while keeping their uniforms securely stored until their return to base.