Quiet (very little click. Almost silent) momentary tactile switch. 6mm x 6mm x 7.3mm - 4.3mm pitch. 

Specification:

• Rating:DC12V 50mA
• Contact Resistance:100m Ω Max
• Insulation Resistance:100M Ω Min
• Withstand Voltage:AC250V(50-60Hz)
• Operation Force:70 ±15gf
• Free Position:9.5 ± 0.15mm
• CR=(OF-CF)/OF *100%;25%±10%
• Pre-Travel:0.25 ± 0.1 mm
• Life Cycles:3000,000 (min)