These are replacement silicon inserts used exclusively for the V2 Otto Kit.  These will change the tension (tighter feel) as the number increases.  These are just the inserts

Description

• V2 White Core (You will use this new core for this kit as opposed to the current one found in your existing V2 kit)
• Red 40 - Lowest Tension
• Orange 50
• Green 60
• Blue 70

These simulate the grommets found in Korean lever