Griarrac Cherry MX Switch Tester 12-Key Mechanical Keyboard Sampler Switch Testing Tool with Keycap Puller and 24 O Rings, 40A-L & 40A-R (Printed PBT Keycap Include Linear Gray) - Newegg.com
Cherry MX Red vs Brown Switches, Red vs Blue O-Rings Review | Taugrim's MMO Blog
photos] My 87 key WASD Custom with Cherry MX Brown and 0.2 mm Red O-Ring. Comes with my designed color scheme and my initials in orange : r/MechanicalKeyboards