Buying Guides
How to Measure a Screw: Diameter, Length and Thread Pitch Explained
M6 × 1.0 × 20 — what do the numbers mean? How to measure screw diameter, length and thread pitch with calipers or a ruler, with a metric pitch chart.
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Buying Guides
How to Choose a Screw Assortment Kit: A Buyer's Guide for Retailers, Distributors and Repair Shops
Buying screw assortment kits for resale or workshop use? Check size coverage, contents, materials, the case and restocking before you order — a practical guide from Boltriver.
Buying Guides
How to Request a Quote for Custom Screws
Request a custom screw quote with a simple checklist covering drawings, dimensions, material, finish, quantity, and delivery.
Buying Guides
304 vs. 316 Stainless Steel Bolts: Which Should You Choose?
Compare 304 and 316 stainless steel bolts for corrosion resistance, strength, and cost. Learn when to specify A2-70 or A4-70 and what to include in an RFQ.
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Machine Screws
304 Stainless Steel Phillips Pan Head Machine Screw - M6 × 75
Phillips pan head machine screw in 304 stainless steel, with a chamfered head edge. Thread diameter M6, thread pitch 1mm, thread length 74.5–75.1mm, head diameter 12.3–12.6mm, head thickness 2.7–2.9mm. Measurements from one batch are for reference only. Small MOQ — orders start from just 1 piece. To request a quote, send us the kit reference or a product photo, the quantity you need, and your delivery country.
Hex Socket Screws & Bolts
304 Stainless Steel Socket Head Cap Screw - M4 × 50
Socket head cap screw in 304 stainless steel (A2-70), with a hex socket drive. Thread size M4, length under head 50mm, head height 3.82–4.00mm, head diameter 6.78–7.22mm, hex socket across flats 3.02–3.08mm. Measurements from one batch are for reference only. Small MOQ — orders start from just 1 piece. To request a quote, send us the kit reference or a product photo, the quantity you need, and your delivery country.
Screw, Nut & Washer Assortment Kits
KM Cross Countersunk Head Machine Screw, Nut & Washer Box Kit
Cross countersunk head machine screws with matching nuts and flat washers in a compartment box kit. Type A: 10 cells; Section B: 15 cells; Kit C: 24 cells. Includes M2, M3 and M4 screws in assorted lengths with matching nuts and washers. M stands for diameter and * for length (mm). Small MOQ — orders start from just 1 piece. To request a quote, send us the kit reference or a product photo, the quantity you need, and your delivery country.