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Replacement Knobs
Stainless Steel

For the correct length brass plunger, select whether this is for an old counterweight without a countersink for the knob, or the newer counterweights with a countersink. You can also order just the knob.


Shipping in USA

Outside the USA

For Counterweights with

14.5 lb. weight with New Low-Profile Stainless Steel Knob
click for larger image

Stainless Steel Counterweights
for Astro-Physics 900GTO, 1200GTO & Mach1*

These stainless steel counterweights fit a 1.875" dia. shaft.

Each weight has rounded edges, a bronze bushing, and a non-rotating brass plunger to prevent scarring of the counterweight shaft. The brass plunger has a stainless steel spring so it retracts when you loosen the thumbscrew. On other companies' weights the plunger falls into the bore. and prevents it from going on the shaft - unless the knob is down.

*Mach1 must have optional 1.875" dia counterweight shaft.

Stainless Steel Knobs

Machined from solid stainless steel , these new low-profile knobs knobs are less likely to snag cables, and more likely to survive being dropped on concrete. They also look good.

Old counterweights can be upgraded with the new knobs.

The weights come in three sizes with your choice of knobs:

7 lbs
1" long x 6" dia.
for 1.875" dia. shaft


Shipping in USA

Outside the USA

Sold Out
14.5 lbs.
2" long x 6" dia.
for 1.875" dia. shaft


Shipping in USA
Sold Out
21.7 lbs.
3" long x 6" dia.
for 1.875" dia. shaft


Shipping in USA
Sold Out

Priority Mail Large Flat-Rate Box is used for each counterweight. Two AP1-7lb-S will fit in one box. Otherwise, they ship individually.

Shipping Charges are for the Continental 48 States. Contact me with your Zip code for costs to Hawaii, Alaska.

International Orders: please contact me for an estimate on shipping costs. Please provide your shipping address and phone number. I will need the phone number for customs, and often forget to ask for it until I start filling out the customs paperwork. We ship USPS EMS. Payment can be made by Bank Wire Transfer, or PayPal.com for most countries.

Sales Tax will automatically be added to orders from California residents.

Replacement Knobs
Stainless Steel

Select whether this is for an old counterweight without a countersink for the knob, or the newer counterweights with a countersink. Knobs will stick up 1/4" higher on old counterweights.


Shipping in USA

Outside the USA

Contact me about availability

Order by Mail

If you would rather not order online, be sure to include your:
Email Address
UPS Shipping Address
List of Product Codes and Quantities
of the items you are ordering.

Send a cashier's check or money order to:

Astro Accessories from RobinCasady.com
316 Mid Valley Center, Suite 112
Carmel, CA 93923

The payment must cover shipping costs (and tax if shipped to CA).

It will save me time and insure accuracy if you will email your shipping address, and phone number to me when you send the money order. Then be sure to include your email address with the money order. That will help me find the email with your address. Thanks.

If you have questions, email me first.

Don't know how much weight you need? Perhaps this will help.

Need a replacement knob?

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