DIN 188 T-Head Bolts
With Double Nip
Standard Weight Chart
What Is a DIN 188 T-Head Bolts With Double Nip
A standard T-head bolt (DIN 261) clamps well, but its rectangular head still has a small amount of rotational freedom inside the T-slot — enough that repeated vibration, impact loading, or a workpiece that shifts under cutting force can gradually twist the bolt out of its intended orientation. DIN 188 addresses that specific failure mode by adding two small projecting nips to the underside of the T-head, positioned to bite into the flanks of the T-slot as the bolt is tightened.
Once seated, the nips lock the head’s rotational position — the bolt can still be loosened and retightened normally, but it won’t creep or spin under sustained vibration the way a plain T-head bolt can. That makes it the better choice for press tooling, high-vibration machine tool fixturing, or any clamping setup that gets torqued and re-torqued many times over its service life.
Akbar Fasteners Pvt. Ltd. manufactures DIN 188 T-head bolts in-house at our Mumbai facility, under ISO 9001:2015, with full mill test documentation, and exports this range to over 50 countries.
Where DIN 188 Bolts Genuinely Earn Their Place
Anti-Rotation Under Vibration
The double nip bites into the T-slot flank so the bolt holds its clamping orientation through sustained vibration or repeated impact loading.
Consistent Dimensional Tolerance
Head width, height, and shank dimensions held to DIN 188 tolerance so the same size bolt fits reliably across tables rated to the same slot standard.
Full Size & Weight Reference
A published dimension and weight chart lets you plan freight, packaging, and slot compatibility before placing an order — not after.
Multiple Material & Grade Options
Mild steel and stainless steel available across common property classes, matched to fixturing load and workshop environment.
DIN 188 T-Head Bolt Dimension & Weight Chart
Standard nominal dimensions and approximate weight by thread size — head width (b) and head height (k) are the two figures to check first against your table’s T-slot size before ordering. Weight is given per piece at a 50mm reference shank length; actual weight scales with the ordered length and should be recalculated for your final bill of materials.
| Thread Size (d) | Head Width (b) | Head Height (k) | Head Length (e) | Recommended T-Slot | Approx Weight/pc @ L=50mm |
|---|---|---|---|---|---|
| M6 | 13 mm | 6 mm | 16 mm | 8 mm | ~0.015 kg |
| M8 | 16 mm | 7 mm | 20 mm | 10 mm | ~0.025 kg |
| M10 | 18 mm | 8 mm | 22 mm | 12 mm | ~0.040 kg |
| M12 | 22 mm | 10 mm | 28 mm | 14 mm | ~0.065 kg |
| M16 | 28 mm | 12 mm | 34 mm | 18 mm | ~0.120 kg |
| M20 | 34 mm | 14 mm | 40 mm | 22 mm | ~0.205 kg |
| M24 | 40 mm | 16 mm | 48 mm | 28 mm | ~0.320 kg |
| M30 | 48 mm | 19 mm | 56 mm | 36 mm | ~0.545 kg |
| M36 | 56 mm | 22 mm | 64 mm | 42 mm | ~0.825 kg |
Figures shown are representative reference values in steel for quick planning purposes, slightly heavier than a plain DIN 261 T-head bolt of the same size due to the added nip material. Please confirm exact dimensions against the current DIN 188 standard document or your engineering drawing, and request our certified dimensional data sheet, before finalizing a purchase order.
T-Slot Fixturing Fastener Range
T-Head Bolts With Double Nip
Anti-rotation T-slot clamping bolts in mild steel and stainless, M6 to M36, custom length to drawing.
DIN 261Standard T-Head Bolts
Plain T-head bolts for general T-slot clamping where anti-rotation isn’t a specific requirement.
DIN 508 / 787T-Slot Nuts
Rectangular clamping nuts sized to match standard T-slot widths for fixture and tooling assembly.
Clamping KitsStep Blocks & Clamps
Adjustable step blocks and clamp plates supplied as complete workholding sets for milling and fixturing.
DIN 188 Technical Overview
Available Materials
- Mild / Carbon Steel Standard Offering
- Stainless Steel 304 / 316 on Request
- Alloy Steel Higher Load Applications
- Surface Finish Black Oxide / Zinc Plated
- Custom Material To Specification
Mechanical Grades
- Property Class 4.6 General Fixturing
- Property Class 8.8 Higher Clamping Load
- Stainless A2/A4 Corrosion Resistant
- Threading Metric Coarse (Standard)
- Testing MTC / NABL on Request
Available Dimensions
- Thread Diameter M6 – M36
- Shank Length Custom to Drawing
- Head Style T-Head With Double Nip
- T-Slot Reference Per DIN 650
- Packaging Loose / Boxed / Palletized
Application Areas
Wherever a T-slot clamped joint faces vibration or repeated re-torquing.
Machine Tool Fixturing
table workholding
Press Tooling & Die Sets
under repeated cycling
High-Vibration Fixturing
sustained machine vibration
CNC Vice & Clamp Mounting
clamping systems to tables
Foundry & Pattern Shop
fixture clamping
Packaging Machinery
clamped to base frames
Metrology & Inspection Tables
gauging & inspection setups
Assembly Line Tooling
for line changeovers
Standard Export Documentation
Prepared as standard practice for every T-head bolt shipment.
Mill Test Certificate (MTC)
Material composition and mechanical property verification for every production batch.
Certificate of Conformance
Confirms the shipment matches the purchase order specification, size, and grade in full.
Certificate of Origin (COO)
Confirms India as country of manufacture for destination customs purposes.
Commercial Invoice & Packing List
Itemized value, Incoterm, and detailed carton/weight breakdown for customs clearance.
Dimensional Data Sheet
Certified head width, height, and nip dimension data against DIN 188 available on request before order confirmation.
Bill of Lading
Ocean or air freight shipping document confirming carrier, mode, and consignee details.
Internationally Recognised Standards Coverage
Related Fastener Grades & Standards
DIN 261 T-Head Bolts
The base T-head bolt standard without the anti-rotation nip, for general T-slot clamping.
View DIN 261 →DIN 258 Taper Pins
Removable, externally threaded taper pins for precision alignment applications.
View DIN 258 →Stainless Steel 316 Fasteners
Corrosion-resistant option for T-head bolts and general fastening in washdown or humid environments.
View SS 316 →Top Nickel Fasteners Manufacturer
See our full in-house nickel alloy manufacturing and documentation capability.
View Manufacturer Page →Send Us Your
T-Slot Size & Load Requirement
Tell us your T-slot width, material preference, and quantity — we’ll confirm the correct DIN 188 size and issue a certified dimensional data sheet with your quote. Akbar Fasteners Pvt. Ltd. responds within 24 hours.
Sales: +91 724 0000 733 · Support: +91 800 9315 333 · sales@akbarfasteners.in