The SD-2 offers two distinct overdrive circuits in a single enclosure, making it a flexible choice for players who want both rhythm crunch and lead saturation at their feet. Each mode—Crunch and Lead—has its own set of controls, letting you dial in separate tones for different playing styles or signal chains.

• Crunch mode: tight, textured overdrive suited for rhythm work
• Lead mode: smooth, higher-gain voicing with added sustain
• Independent Level, Tone, and Drive controls for each mode via concentric knobs
• Mode switching via onboard footswitch or optional FS-5L remote
• LED indicators: Green for Crunch, Red for Lead
• Stereo-compatible jacks: Input, Output, Remote
• Powered by 9V battery or Boss PSA adapter
• Dimensions: 70 x 125 x 55 mm Weight: 420g

This unit is in solid shape overall, with only a few minor chips in the yellow powder-coated finish—typical for a pedal of its age and use. The enclosure remains clean and structurally sound, and all functions operate as expected. A dependable dual-drive pedal from Boss's golden era.