Over 87,000 Standard Mechanical Components
- Precision and Commercial
- Inch and Metric
- Small Quantities to Large Production Runs
Custom design and Assemblies – Our engineers are always available for free technical support and design consultation.
Request your FREE Inch and Metric catalogs, more than 2,784 pages of parts, specifications and technical data

DRIVE COMPONENTS
Industrial Timing Belts:
Standard WidthsCustom Widths
Cables Accessories:
Timing Belt Clamps
Timing Belt Tension Meters
Timing Belt Tensioners
Pulleys:
Offered in both metal and plastic to match belt profilesWide variety of miniature pulleys and matching timing belts.
Can be customized to your specifications
SDP/SI Engineers are power transmission design specialists
Ladder Chain and Roller Chain:
For Light Duty to Heavy Duty ApplicationsMetal and Self-Lubricating Plastic
Sprockets:
Offered in metal and plasticSub-miniature, miniature and small sizes

GEAR DRIVES
Precision and Commercial Gears:
Spur GearsAnti-Backlash Gears
Mini-Lash Gears
Pinions
Gear Racks
Round Gear Racks
Internal Gears
Miter and Bevel Gears
Anti-Backlash Worm Gears
Worm Gears and Worms
Gear Clamps
Differentials
Custom Design and Assemblies

GEARHEADS & SPEED REDUCERS
Bu-Ord Sizes 8 – 18Planetary Gearheads
Spur Gearheads
Custom design and manufactured to your specs

RIGHT-ANGLE GEAR DRIVES & SPEED REDUCERS
Bevel GearboxesWorm and Bevel Gear Drives
Worm Gear Speed Reducers
Helical Gear Speed Reducers
Miniature Gear Drives
Standard Components and Build-to-Print Custom Parts and Assemblies

SHAFT COUPLINGS
Rigid Shaft Couplings:
Flexible Shaft Couplings:
Heavy-Duty Flexible CouplingsMiniature Bellows Type Flexible Couplings
Modular Bellows Type Flexible Couplings (build to meet your specific need)
Powerful Magnetic Disk Couplings

VIBRATION & SHOCK ABSORBING COMPONENTS
Miniature, lightweight shock absorbing components for instrumentation, camera mounts and other high-tech applicationsHeavy-duty machine mounts for industrial applications
Vibration reduction mounts for HVAC

Established in 1950, SDP/SI is the leading manufacturer and supplier of high-quality machined parts, molded components, precision gears and gear assemblies. Industries from all sectors rely on SDP/SI for small mechanical components and sub-assemblies. SDP/SI precision parts are used worldwide in robotics for medical instrumentation to surveillance systems; antenna positioning in satellites; door releases and stabilization systems in commercial and military jets; actuation/positioning systems and weapons targeting for tanks and missiles. Get the high-quality service and mechanical components your design requires at SDP/SI.
Bearings Brakes & Clutches Chains & Sprockets Couplings & Flexible Shafts Fairloc® Components Gearheads & Speed Reducers Gears Hardware & Miscellaneous Components Linear Guide Systems Miniature Belts & Pulleys Miniature Gears Miniature Shaft & Shaft Accessories Motors Right Angle Drives Rollers - Feed & Idler Shafts & Accessories Shaftloc® & Accessories Synchromesh Drive Systems Timing Belts & Cables GT® Timing Belts HTD® Timing Belts 40 D.P. Timing Belts MXL Timing Belts XL Timing Belts L Timing Belts Timing Belt Profile (Detail) Timing Belt Pulleys Universal Joints Vibration Mounts Capabilities