Products for bench top machinists | LittleMachineShop.com

Key, 3x8 mm

Key, 3x8 mm - Main image
$0.69 $0.95 In stock

Key, 3x8 mm is a small machine key intended for bench top machining and mechanical assembly work. It is listed under the Sieg Industrial Group brand and is identified by the standard SKU code 1357.

  • Product name: Key, 3x8 mm
  • Size designation: 3x8 mm
  • Brand: Sieg Industrial Group
  • SKU: 1357
  • Standard option: Standard

This key is suited to fitting and repair tasks where a 3x8 mm key is required. Confirm the size and fit needed for your specific application before ordering.

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Standard Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

Express Shipping: Handling (business days) 0–1; Transit (business days) 7–15.

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Delivery costs

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Standard Shipping · United States: $0.00

Express Shipping · United States: $3.99

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Returning an item

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (5.0 / 5 · 5 reviews)

Ava F. ★★★★★

I use these keys to align pulleys on my mini lathe, and the 3x8 mm fit snugly without any filing needed. They're consistent across the batch, which saves time during assembly.

Daniel A. ★★★★★

The 3x8 mm size was exactly what I needed for a tight gear assembly—no filing or adjusting required. It held secure under steady torque without any signs of wear after a full day of use. I’m glad I matched the spec to the SKU.

Miles X. ★★★★★

Slid perfectly into both the shaft and hub keyways on my milling machine setup with no filing required. The 3x8 mm dimensions were spot on and the metal has a solid, clean feel.