KT Fat Springs - 20.5mm

The longer a spring's length, the more compressed it will be once installed in a switch. This means that the switch will feel heavier at the start of the key-press, however, it will also feel more consistent throughout the keystroke.

These springs are visually different to the standard and KT calls them "Fat Waist Springs".

Description taken from KT's product page:
We've designed a longer progressive spring with a wider coil diameter in the middle and tighter coils toward the ends. The changing coil diameter and pitch are intended to produce a more controlled force curve and stable rebound, particularly as the switch approaches bottom-out. The spring is 20.5 mm long and uses KOS precision spring wire. The middle of the spring is approximately 0.4 mm larger in diameter than the ends.

• Quantity: 100 Springs
  
• Length: 20mm
• Tolerance: +/- 2g
  
• Manufacturer: KT / Kaidi
  
• Rated at Bottom Out
  

Kaidi is a reputable company in China who produces spring and wire products for many popular switch manufacturers.

Their aftermarket springs are very popular in the Eastern community because they’re economical, cost-effective and great value.

The springs are produced with low variance and high accuracy which do not deviate beyond ±2g. For reference, standard spring tolerances usually vary between ±5g to ±20g.

Need some tips or advice on what springs to choose?
Read this Blog Post: 
What Keyboard Springs Should I buy?