# HELIFOUNER \#4-40 Nylon Insert Hex Lock Nuts, 50-Piece Set

HELIFOUNER \#4-40 nylon insert hex lock nuts are a 50-piece set made for matching coarse-thread fasteners. The listing specifies 304 stainless steel and describes a nylon collar intended to reduce loosening from vibration and torque.

- [Original product page](https://best-deals.pro/product/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [View offer](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- Market: US
- Language: en-US
- Currency: USD
- Brand: HELIFOUNER
- Model: HELIFOUNER-lock-nuts
- Category: Tools & Garden > Hardware & Building Materials
- Price: 3.49 USD
- Previous price: 6.99 USD
- Discount: 50%
- Price checked: 2026-11-12T11:12:37.365Z
- Rating: 4.5 / 5
- Reviews: 87

Prices and deal status are the latest recorded data, not a guarantee of availability. Confirm the price and availability with the store.

## At a glance

- Nylon insert collar is described as helping resist loosening under vibration and torque.
- Coarse \#4-40 thread, fully threaded body and external hex drive.
- Listing identifies the nuts as 304 stainless steel and silver-colored.

## Pros

- A 50-piece quantity suits small assemblies and repair work using the specified thread size.
- Nylon insert design provides a locking feature without requiring a separate locking washer, according to the listing.
- Stainless-steel construction is specified for applications where corrosion resistance is a consideration.

## Specifications

### Identity
- Brand: HELIFOUNER
- Model: HELIFOUNER-lock-nuts
### Thread and design
- Thread size: \#4-40
- Thread type: Fully Threaded
- Thread style: Right Hand
- Thread class: Coarse
- Hex style: Hexagonal
- Drive style: External Hex
- Compatible groove diameter: 0.16 inches
- Fastener type: Lock
### Materials and finish
- Material listed: Stainless Steel
- Grade rating: 304 Stainless Steel
- Color: Silver
- Finish type: Polished
### Pack and weight
- Number of pieces: 50
- Weight listed: 0.04 kg

## Before you buy

- Confirm that \#4-40 coarse threads match the mating bolt. The listing describes 50 nuts packed in a plastic case, while its package-included description names only the nuts, so whether a case is included is unclear. The stated corrosion and vibration performance are manufacturer claims, not independently verified.

## A good fit for

- Small repairs and assemblies using compatible \#4-40 coarse-thread bolts.
- Buyers seeking nylon-insert locking nuts in a 50-piece quantity.

## Less suited to

- Projects requiring a thread size other than \#4-40 or a non-coarse thread.

## Customer feedback

Aggregate ratings lean positive, with most ratings in the five-star category, but a smaller share falls in lower categories. No written customer feedback is supplied, so the ratings do not establish why buyers were satisfied or dissatisfied. For a small fastener set, buyers should judge fit against the specified \#4-40 thread rather than infer performance from the overall rating.

## Frequently asked questions

### What thread size are these nuts?
The listing specifies \#4-40 coarse thread. Match the size and pitch to the bolt before ordering.
### How many nuts are included?
The listing states a quantity of 50. It describes a plastic case in one feature, but the package-included wording lists the nuts alone, so case inclusion is uncertain.
### What does the nylon insert do?
The listing says the collar is intended to reduce loosening under vibration and torque. It does not provide independent performance testing.
### What material is listed?
The product details list stainless steel, and the title and description specify 304 stainless steel.

## Alternative options

- [Vifmy \#6-32 Lock Nut, 190Pcs Stainless Steel Nylock Insert Locking Nuts \| 6-32 in locknut,nylon insert hex nuts 304 SS A2-70, standard sae thread nylock nut vibration resistant for bolts,machinery](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [25 Pcs Retro-Motive Emblem & Trim PAL Nuts,Fits 3/16" Studs- 3/8" Hex Replacement \#1303](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [Dorman Help\! 45384 Thread Cutting Nuts Asst,Silver](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [135 Pack 304 Stainless Steel A2-70 Nylon Insert Lock Nuts, SAE & Metric \| M3 M4 M5 M6 M8 M10 M12 \#6-32 \#8-32 \#10-24 1/4-20 5/16-18 3/8-16 1/2-13, Anti-Loose for Industrial & Home Fastening](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [Emblem & Trim PAL Nuts,Fits 3/16" Studs- 3/8" Hex Replacement GM 1303 \(Fits 3/16" Studs-30PCS\)](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [258PCS UIETUIL 8 Sizes Internal Tooth Star Lock Washers Kit, M2.5-12 304SS \| M2.5 M3 M4 M5 M6 M8 M10 M12 Quick Speed Push Lock Nuts Retaining Clips, 304 Stainless Steel](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [Fullerkreg 1/4-20 Nylon Insert Hex Lock Nuts, 50Pcs \| 18-8 Stainless Steel /A2/Plain Finish](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [250 Pieces M3 x 0.5mm Nylon Insert Hex Lock Nuts, 304 Stainless Steel \(18-8\) Locknu...](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [50Pcs 1/4-20 Lock Nuts, Nylon Insert Locknuts 304 Stainless Steel 18-8 SS Black Zin...](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [50Pcs \#10-24 Lock Nuts, Nylon Insert Locknuts 304 Stainless Steel 18-8 SS Self-Lock...](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [M6 x 1.0mm Nylon Insert Hex Lock Nuts 50Pcs 304 Stainless Steel Locknuts, Hex Drive...](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [\#10-24 Nylon Lock Nuts, 304 Stainless Steel \(18-8\) Hex Insert Locknuts, UNC Coarse Thread, Precision Nuts for 3D Printers & Electronics, 50 Pack](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)

## Add-ons

- [LUPANTER 5/16" Inch Stainless Flat Washers 100 Pack Made of 18-8 \(304\) Stainless Steel……](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)
- [Mellewell \#6-32 x 5/8" Truss Head Machine Screws, Full Thread, 18-8 Stainless Steel, Quantity 100](https://best-deals.pro/visit/helifounner-4-40-nylon-insert-hex-lock-nuts-50-piece)

## Images

![HELIFOUNER \#4-40 Nylon Insert Hex Lock Nuts, 50-Piece Set — 1](https://best-deals.pro/i/DNu2357M4zQb-nWkGio0FDMxekWje3V2-xhOcfOnYy6CvWS21XjAi1S1aopzp3FR25aFakV1ZptjAotaFp2m7ENlT0UlVX_co9mD9XoHTyC79TAeLBEN.jpg)

![HELIFOUNER \#4-40 Nylon Insert Hex Lock Nuts, 50-Piece Set — 2](https://best-deals.pro/i/RupLxwnyxbL57bjzgStF8cNyk-ynLb2J32dLkIY1ycBA2P0zBRXAXBCIGv5vKdXv9r3ICsOrMa6pqC2et_eUVcQulTUua4SniUxb_7lbTEGXzCQMuGdV.jpg)

![HELIFOUNER \#4-40 Nylon Insert Hex Lock Nuts, 50-Piece Set — 3](https://best-deals.pro/i/B78DY88CieYzT2B6GVgBFA4o01SxsW-Y7RFS8nUmGkZH1yTa_dcJaNHBXQLhOlgtNf9RJwlWOPrlyCylnwLxOhFQiZifejZ3dzEk8mD_qZBM8fnU8bG-.jpg)

![HELIFOUNER \#4-40 Nylon Insert Hex Lock Nuts, 50-Piece Set — 4](https://best-deals.pro/i/8bc_TxfNwcROqS3SH9bgQ-NNyAQJ58Al1Qvb3hhKykqB7SA_3tt9U8twKWyDP_pD-UbZ6NpTLGEPSrUzbWm_FNxHg38t33jO2sr3_s7mWy-2Zhz3YKAy.jpg)

![HELIFOUNER \#4-40 Nylon Insert Hex Lock Nuts, 50-Piece Set — 5](https://best-deals.pro/i/hZOihdXOx2n-I7nL_FDbaBNevyTt8S8tqNjKgIH9YZeEsuDlet8Xf-EILMEZvdgNqOdIRE-_vUOo_iDiHJhbeSfd9TLG8E_NjAvacZwTIirySQlp4ayQ.jpg)

![HELIFOUNER \#4-40 Nylon Insert Hex Lock Nuts, 50-Piece Set — 6](https://best-deals.pro/i/1-9noY4gBYt2tGxvOkR-afVUwBX59n2eUJkb3aeHdGiJ3MKadrkZSlwVk5MNO-Xz-AiXJIPaxngEDtHYErBWXOoya_LlU4ZQYaSzWgQr7rV5so14ddPg.jpg)