Brass is widely favored for long shackle brass padlock bodies because of its excellent material properties, which directly contribute to the lock's longevity and reliability:

Resistance to Rust and Corrosion: Unlike steel or iron, brass does not rust and is highly resistant to corrosion caused by moisture, humidity, and outdoor elements. This makes brass padlocks especially suitable for outdoor use, even in harsh weather conditions.

Longevity: The corrosion resistance of brass ensures that the padlock maintains its strength and appearance over time, reducing the need for frequent replacements or maintenance.

Strong and Durable: While brass is softer than steel, its strength is sufficient for many security applications. When combined with hardened steel shackles (often used in long shackle padlocks), the lock offers robust protection against physical attacks.

Long shackle brass padlocks often come equipped with enhanced security features that contribute to their effectiveness:

Hardened Steel Shackle: Although the body is made of brass, the shackle is frequently constructed from hardened steel, providing greater resistance to cutting, sawing, or prying attempts.

Keyed or Combination Options: These padlocks can be keyed alike, master keyed, or set with combination locks, offering flexible security management options for individuals or organizations.

Pick-Resistant Cylinders: Many models feature advanced locking mechanisms that provide resistance to picking and unauthorized entry, enhancing overall security.

https://www.keeperlock.com/product/brass-padlock/bb600-double-groove-straight-open-brass-padlock.html

ART. NO.    SIZE
BB630    30mm
BB640    40mm
BB650    50mm
BB660    60mm
BB630L    30mm long shackle
BB640L    40mm long shackle