19 products
Sale
Sale
Our experienced shipping department will package your order for secure delivery. We will contact you if your order requires additional attention.
We're here to help – please contact us with any questions.

For guaranteed Next Day, 2-Day or 3-Day delivery, please call our friendly sales team Monday through Friday from 9-5 ET at 800-530-9494.
FREE or Flat Rate offers are available for single shipments to retail customers within the contiguous 48 United States.
Carrier and service type will be chosen by Chassis Shop on any order shipped by FREE or Flat Rate delivery. Please provide your U.S. Postal-specific address if it's different than your UPS address.

Delivery rates, if any, are determined by the size and weight of your
package, service type and destination. You may select your delivery
method of your choice during checkout.
When arranging your own carrier for delivery, leave a message in the shopping cart Order Notes field and choose "Pick Up" as your Shipping Method during checkout. We will contact you to complete the process.

Our package delivery carriers within the United States are UPS and
Post Office Mail.
Some service options may not be available to all areas.

Heavy and oversized shipments may be delivered as Truck Freight.
We will notify you if your order must be shipped by truck.
Truck delivery is 2-14 business days in continental United States.

We ship orders to APO, FPO and DPO addresses using the Post Office.

Estimated Priority Mail (Post Office) Days-in-Transit Map
for the United States from Muskegon Heights, Michigan 49444


Our package delivery carriers for U.S. Territories are UPS and Post Office Mail.
Some service options may not be available to all areas

If shipping to a United States address for pickup or freight forwarding, UPS, Post Office Mail or Truck Freight may be used.

Based your order contents and location, you may be responsible for additional duties, taxes or customs fees that are not represented in the Invoice total. These potential charges are imposed by the destination territory and collected by the carrier prior to delivery.
Our package delivery carrier for Canada and Mexico is UPS including UPS Standard ground service. 
Based your order contents and location, you may be responsible for additional duties, taxes or customs fees that are not represented in the Invoice total. These potential charges are imposed by the destination country and collected by the carrier prior to delivery.
Our package delivery carrier for international orders is UPS.
Some service options may not be available to all areas.

If shipping to a United States address for pickup or freight forwarding, UPS, Post Office Mail or Truck Freight may be used.
Based your order contents and location, you may be responsible for additional duties, taxes or customs fees that are not represented in the Invoice total. These potential charges are imposed by the destination territory and collected by the carrier prior to delivery.
Order tracking and history are archived to the email address used to generate the order.
Simply log into your account to review order history.
Please create an account with the email address used for your orders then log in to review order history.
Our experienced shipping department will package your order for secure delivery. We will contact you if your order requires additional attention.
We're here to help – please contact us with any questions.

For guaranteed Next Day, 2-Day or 3-Day delivery, please call our friendly sales team Monday through Friday from 9-5 ET at 800-530-9494.
FREE or Flat Rate offers are available for single shipments to retail customers within the contiguous 48 United States.
Carrier and service type will be chosen by Chassis Shop on any order shipped by FREE or Flat Rate delivery. Please provide your U.S. Postal-specific address if it's different than your UPS address.

Delivery rates, if any, are determined by the size and weight of your
package, service type and destination. You may select your delivery
method of your choice during checkout.
When arranging your own carrier for delivery, leave a message in the shopping cart Order Notes field and choose "Pick Up" as your Shipping Method during checkout. We will contact you to complete the process.

Our package delivery carriers within the United States are UPS and
Post Office Mail.
Some service options may not be available to all areas.

Heavy and oversized shipments may be delivered as Truck Freight.
We will notify you if your order must be shipped by truck.
Truck delivery is 2-14 business days in continental United States.

We ship orders to APO, FPO and DPO addresses using the Post Office.

Estimated Priority Mail (Post Office) Days-in-Transit Map
for the United States from Muskegon Heights, Michigan 49444


Our package delivery carriers for U.S. Territories are UPS and Post Office Mail.
Some service options may not be available to all areas

If shipping to a United States address for pickup or freight forwarding, UPS, Post Office Mail or Truck Freight may be used.

Based your order contents and location, you may be responsible for additional duties, taxes or customs fees that are not represented in the Invoice total. These potential charges are imposed by the destination territory and collected by the carrier prior to delivery.
Our package delivery carrier for Canada and Mexico is UPS including UPS Standard ground service. 
Based your order contents and location, you may be responsible for additional duties, taxes or customs fees that are not represented in the Invoice total. These potential charges are imposed by the destination country and collected by the carrier prior to delivery.
Our package delivery carrier for international orders is UPS.
Some service options may not be available to all areas.

If shipping to a United States address for pickup or freight forwarding, UPS, Post Office Mail or Truck Freight may be used.
Based your order contents and location, you may be responsible for additional duties, taxes or customs fees that are not represented in the Invoice total. These potential charges are imposed by the destination territory and collected by the carrier prior to delivery.
Order tracking and history are archived to the email address used to generate the order.
Simply log into your account to review order history.
Please create an account with the email address used for your orders then log in to review order history.
Many combinations, Several colors and Amazing finishes.
Custom-fabricated tanks, Fuel cells, Rear End housings, Valve covers, Overflow tanks, Intercooler ice boxes, Ballast tanks, Inspection viewing ports
19 products
Sale
Sale

Turn heads while working on your race car or hot rod with Pro-werks' signature Easy Turn Fill Caps. Once you've added one of these amazing assemblies, you'll want to install one at every location possible. And you may find yourself checking things more often, just to get your hands on the Easy Turn cap again!
These lightweight, non-vented Pro-werks Fill Caps feature deep finger notches for a positive and comfortable grip, this design is another Pro-werks innovation, appreciated by everyone who uses them.
We start with American melt 6061-T6 billet aluminum: it is precision CNC machined to exacting standards for proper fit and to create the foundation for obtaining amazing finishes and performance.
This design uses a "radial squeeze" action on the Buna O-ring for a secure seal. Precision machined quick-start coarse threads make using these caps a breeze.
The large selection of Pro-werks mounting bungs are crafted fron Steel, Aluminum or Stainless Steel and available in both Weld-in and Bolt-in styles.
To compliment the color combination of your project, the caps are finished off in Pro-werks Brilliance anodized colors in your choice of Black, Red, Blue, or beautifully Micro-Polished aluminum - the finishes ar impeccable!

Easy Turn Fill Caps come in many sizes and are packaged as complete assemblies with your choice of one of the many versatile mounting options, or each component is also available separately.

Popular uses for Easy Turn Fill Caps include:
Be sure to check out the entire line up - Billet aluminum Easy Turn Fill Caps are a Pro-Werks specialty.
You can always count on Pro-Werks to do it right!

We also offer a full line of weld plumbing bungs to complete your project.
Click the images above to view all the options.
You can calculate how many gallons of fluid a tank will hold by dividing the total cubic inch volume by 231. As an example a basic rectangular shaped tank measuring 12"(L) x 12"(W) x 10"(H) = 1440 cubic inches. The next step is to divide the total volume of 1440 cubic inches by 231 = 6.23 gallons.
If your tank is an irregular shape, or has unique features, calculate the cubic inch volume of those areas also, then add or subtract the values to arrive at the total cubic inch volume of your custom fabricated tank.
Note: Welding should always be performed by a qualified welder.
"I use your bolt on caps and bungs on my carbon fiber Cummins common rail valve covers. Love the quality. Thank you."
"I upgraded my fuel cell to an Easy Turn fill cap assembly. It wasn't long until all my friends did the same. Great product!"
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