Send a part number, a photo, or a whole BOM — we supply it and stand behind it. Worldwide shipping to 80+ countries.

3G Electric
RFQ CartGet a QuoteSign inSign up
HAM-LET Compression Fitting Plug: 4 mm OD Fitting Size, Compression - Double-Ferrule Stainless Steel Fittings
HAM-LETDouble-Ferrule Stainless Steel Fittings

HAM-LET Compression Fitting Plug: 4 mm OD Fitting Size, Compression

The HAM-LET Compression Fitting Plug (MPN 7121L-SS-4MM) is a double-ferrule stainless steel fitting for 4 mm OD tubing, part of the LETLOK series. It is compatible with Let-Lok fitting brands, providing a reliable…

SKU 3G-OTH-471304

Brand
HAM-LET
Item
Compression Fitting Plug: 4 mm OD Fitting Size, Compression
Category
Double-Ferrule Stainless Steel Fittings
Available to Order
Trade pricing by quote — replies within 24h
Qty
WhatsApp an engineer
No account needed — your quote request goes straight to our engineers. A free account lets you track quotes and re-order faster.
Worldwide Shipping
Air & sea freight
Datasheet on Request
Technical specs
1-Day Quote
Replies within 24h

Technical Specifications

HAM-LET
Manufacturer Part Number
7121L-SS-4MM
Series
LETLOK
Type
Compression, Stainless Steel
Compatible Fitting Brands
Let-Lok
View Full Spec Sheet

Technical Documents

No technical documents available for this product.
Request documentation →
Not sure this is the right part? Get a recommendation.

Need installation or engineering help?

Installation, commissioning, maintenance plans, system design, and bundled product + service quotes — one team handles the full scope.
Talk to an engineer

Ask a question

HAM-LET Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The HAM-LET Compression Fitting Plug (MPN 7121L-SS-4MM) is a double-ferrule stainless steel fitting for 4 mm OD tubing, part of the LETLOK series. It is compatible with Let-Lok fitting brands, providing a reliable seal in industrial fluid systems.

Frequently Asked Questions

What is a HAM-LET compression fitting plug used for?

A HAM-LET compression fitting plug seals the end of a 4 mm OD tube in industrial fluid systems. It is part of the LETLOK series and uses a double-ferrule design to create a reliable, leak-tight connection in applications such as instrumentation, chemical processing, and hydraulic lines.

What are the specifications of the HAM-LET 7121L-SS-4MM plug?

The HAM-LET 7121L-SS-4MM plug is a double-ferrule stainless steel compression fitting for 4 mm OD tubing. It belongs to the LETLOK series and is compatible with Let-Lok fitting brands. The manufacturer part number is 7121L-SS-4MM, and it is made from stainless steel for corrosion resistance.

Where to buy HAM-LET compression fittings worldwide?

3G Electric supplies HAM-LET compression fittings, including the 7121L-SS-4MM plug, to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time on this and other industrial components across 14 departments.

How to install a HAM-LET double-ferrule compression fitting?

To install a HAM-LET double-ferrule compression fitting, cut tubing squarely, deburr the end, and slide the nut and ferrules onto the tube. Insert the tube into the fitting body until it bottoms out, then tighten the nut to the manufacturer's recommended torque. Always follow generic best practices for leak testing.

Used in

Common applications for HAM-LET
Oil and gas — HAM-LET H99 Series needle valves for instrument isolation in high-pressure lines
Chemical processing — HAM-LET H-400 Series check valves for backflow prevention in corrosive fluid systems
Semiconductor manufacturing — HAM-LET EVZS4R-BV diaphragm valves for ultra-high-purity gas distribution
Power generation — HAM-LET H-6800 Series three-way ball valves for cooling water flow switching
Analytical instrumentation — HAM-LET H300U Series metering valves for precise flow regulation in lab gas systems
Hydraulic systems — HAM-LET H-410 Series poppet check valves for load-holding in hydraulic circuits

HAM-LET Products

3G Electric supplies HAM-LET double-ferrule stainless steel fittings. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

You might also need

Burners & Combustion →Pumps & Compressors →Spare Parts →All Products →

More from HAM-LET

View all HAM-LET parts →
HAM-LET Compression Fitting Adapter: 8 mm OD x 1/4 in Pipe Fitting Size, Compression x MNPT (MPN 768L-SS-8MM X 1/4). Key specifications — Compatible Fitting Brands: Let-Lok; Brand: HAM-LET.
HAM-LET
HAM-LET Compression Fitting Adapter: 8 mm OD x 1/4 in Pipe Fitting Size, Compression x MNPT (MPN 768L-SS-8MM X 1/4). Key specifications — Compatible Fitting Brands: Let-Lok; Brand: HAM-LET.
HAM-LET Compression Fitting Adapter: 1/2 in OD x 3/4 in Pipe Fitting Size, Tube x MNPT (MPN 769L SS 1/2 X 3/4). Key specifications — Series: Let-Lok; Compatible Fitting Brands: Swagelok; Brand: HAM-LET; Fitting Size: 1/2 in OD x 3/4 in Pipe.
HAM-LET
HAM-LET Compression Fitting Adapter: 1/2 in OD x 3/4 in Pipe Fitting Size, Tube x MNPT (MPN 769L SS 1/2 X 3/4). Key specifications — Series: Let-Lok; Compatible Fitting Brands: Swagelok; Brand: HAM-LET; Fitting Size: 1/2 in OD x 3/4 in Pipe.
HAM-LET Compression Tee Fitting: 3/8 in OD x 1/4 in Pipe x 3/8 in OD Fitting Size, Stainless Steel (MPN 771L SS 3/8 X 1/4). Key specifications — Series: Let-Lok; Compatible Fitting Brands: Parker A-LOK; Brand: HAM-LET.
HAM-LET
HAM-LET Compression Tee Fitting: 3/8 in OD x 1/4 in Pipe x 3/8 in OD Fitting Size, Stainless Steel (MPN 771L SS 3/8 X 1/4). Key specifications — Series: Let-Lok; Compatible Fitting Brands: Parker A-LOK; Brand: HAM-LET.
HAM-LET Compression Fitting Adapter: 12 mm OD x 1/4 in Pipe Fitting Size, Tube x MNPT (MPN 739LM SS 12MMX 1/4). Key specifications — Compatible Fitting Brands: Swagelok; Brand: HAM-LET.
HAM-LET
HAM-LET Compression Fitting Adapter: 12 mm OD x 1/4 in Pipe Fitting Size, Tube x MNPT (MPN 739LM SS 12MMX 1/4). Key specifications — Compatible Fitting Brands: Swagelok; Brand: HAM-LET.
HAM-LET Compression Fitting Adapter: 14 mm OD x 1/2 in Pipe Fitting Size, Compression x FNPT (MPN 766L SS 14MMX 1/2). Key specifications — Compatible Fitting Brands: Swagelok; Brand: HAM-LET.
HAM-LET
HAM-LET Compression Fitting Adapter: 14 mm OD x 1/2 in Pipe Fitting Size, Compression x FNPT (MPN 766L SS 14MMX 1/2). Key specifications — Compatible Fitting Brands: Swagelok; Brand: HAM-LET.
HAM-LET Compression Fitting Adapter: 3/8 in OD x 3/8 in OD Fitting Size, Tube x Tube (MPN 767LP SS 3/8). Key specifications — Series: Let-Lok; Compatible Fitting Brands: Swagelok; Brand: HAM-LET.
HAM-LET
HAM-LET Compression Fitting Adapter: 3/8 in OD x 3/8 in OD Fitting Size, Tube x Tube (MPN 767LP SS 3/8). Key specifications — Series: Let-Lok; Compatible Fitting Brands: Swagelok; Brand: HAM-LET.
HAM-LET Compression Tee Fitting: 1/8 in OD x 1/8 in OD x 1/8 in Pipe Fitting Size, Stainless Steel (MPN 772L SS 1/8 X 1/8). Key specifications — Series: Let-Lok; Compatible Fitting Brands: Parker A-LOK; Brand: HAM-LET.
HAM-LET
HAM-LET Compression Tee Fitting: 1/8 in OD x 1/8 in OD x 1/8 in Pipe Fitting Size, Stainless Steel (MPN 772L SS 1/8 X 1/8). Key specifications — Series: Let-Lok; Compatible Fitting Brands: Parker A-LOK; Brand: HAM-LET.
HAM-LET Compression Fitting Adapter: 20 mm OD x 20 mm OD Fitting Size, Compression x Compression (MPN 767LP SS 20MM). Key specifications — Compatible Fitting Brands: Swagelok; Brand: HAM-LET.
HAM-LET
HAM-LET Compression Fitting Adapter: 20 mm OD x 20 mm OD Fitting Size, Compression x Compression (MPN 767LP SS 20MM). Key specifications — Compatible Fitting Brands: Swagelok; Brand: HAM-LET.