1 Set of 3 Plastic Knobs for Preamp Control, Bass JB Effect, Black (2 Large, 1 Small) Clear replacement knobs designed for bass preamp and effect controls. These three black plastic knobs provide a simple, reliable way to restore or the control layout on JB style bass preamps and compatible effect units. Key benefits Restores control functionality: worn, cracked, or missing knobs to regain precise access to volume, tone, and blend settings. Keeps a consistent look: Two larger knobs and one smaller knob match common control arrangements on bass preamp panels and effect units. Easy to install: Pushon design allows quick swap without soldering or special tools. What it does Provides tactile control for preamp settings on bass JB style instruments and related effect units. Two large knobs are suited for primary controls such as volume and tone. One small knob works well for secondary controls such as balance, blend, or midshift. Key attributes Material: Plastic construction for lightweight durability. Color: Black for discreet, professional appearance. Set contents: 3 knobs total, arranged as 2 large and 1 small to match typical preamp control layouts. Function: Replacement or upgrade for preamp control knobs on bass JB style preamps and compatible effect devices. Compatibility Intended for use with JB style bass preamps and compatible effect units that use pushon control knobs. Suitable where a twolargeplusonesmall control arrangement is required. Performance and handling Provides reliable grip and control for routine adjustments during practice and performance. Lightweight design maintains original panel balance and responsiveness. Practical use scenarios : Swap out damaged knobs on a bass preamp to restore complete control operation before a gig or studio session. : original knobs to achieve a consistent black control panel look across pedals and preamps. Workshop upgrade: Keep a spare set on hand for quick field repairs or adjustments during setups and maintenance. Simple installation tips Verify the knob fits the control shaft type on your unit before pressing on. Align splines or Dshaft flat side, then push the knob onto the shaft until seated. If fit is loose, check shaft condition or consider using a replacement knob specific to the shaft specification. Contents of package 3 plastic control knobs, black: 2 large, 1 small. This set provides a straightforward, practical option for replacing or matching preamp control knobs on JB style bass preamps and compatible effect units without unnecessary complexity.