Bass, Middle and Treble control knobs Built-in tuner with LED display Phase switch Size: 2.20 "W x 3.3" L x 1.625 "D (55.8mm x 84.2mm x 41.3mm) Hole size: 2.0 "W x 2.662" L (50.8mm x 67.62mm) Screw spacing: 1.785 "W x 2.795" L (45.34mm x 71mm) Package included: 1*301 pickup 1*Connecting wire tail nail 1*Tag label 1*User manual 1*Tie strap 1*Trunk fixing frame 4*screws 2*Mounting brackets Package List 1 1. The classic Presys Blender is small in size. 2 2. Suitable for many guitar volume control bass, midrange and treble control knobs with LED display built-in tuner phase switch unique pivot design. 3 3. Immediate access to Sonicore pickups with 9 volt battery pre-wired, no soldering required. 4 4. Plug and play installation low profile control knob Battery life: 88 hours onboard anti-feedback control. 5 5. Luster control can realize other sound adjustments. The built-in microphone kit with microphone mixing level control includes: preamplifier with Sonicore flexible piezoelectric pickup, built-in microphone and internal pin output jack, mounting screw. 6