Add-on Cast Iron Sash Weights

Manufacturer: SRS Hardware

(3 customer reviews)

Note: Due to the heavy nature of this item, a custom shipping quote for each order must be calculated and weight orders are not returnable. Please complete our weight request form below to receive a quote including shipping.

Weight orders are ineligible for the Trade Professional discount.

$3.60 per pound

Case includes 24 pieces, $43.20/case

SKU: AOW Category:


SRS Hardware has come up with a great new product, “Add-on Sash Weights”.

Have you ever been vexed by a lower sash that won’t stay open, or an upper sash that has a “mind of its own” and wants to slowly slip down?  This is a common and annoying phenomenon often caused when broken glass is replaced with slightly thicker (thus heavier) glass.  They are simple to install and do not require disconnecting your existing weights from the sash chain or cord.

Each SRS AOW (add-on weight) ½ pound weight consists of a 1-3/8” diameter cast iron body and a CNC machined steel taper pin. The body has a ½” diameter hole through the center and a slot along its length allowing it to simply slip onto the sash cord or chain without having to unfasten the existing weight. Dropping the taper pin into the top of the slot firmly locks the weight onto the chain. Multiple AOW’s can be stacked in order to arrive at the perfect weight. Once you have removed the weight pocket cover and have access to the sash cord, installing the weights takes under 10 seconds each. We have kept the diameter small to be certain that the weights are suitable for residential sash and will fit easily through narrow residential weight pocket covers.

AOW weights are offered in 24 piece cases. $3.60/lb

SRS keeps plenty of cases in stock for immediate shipment.

    Add On Weights Quotation Request

    Additional information


    $3.60 per pound

    Case Size

    AOW 24: .5 lb weights, 24 pieces


    Cast Iron, Steel


    All weights are 1-3/8” diameter


    SRS Hardware


    Installing SRS Hardware Add On Weights

    After restoring and reinstalling these Victorian double hung window sashes we found the original pocket weights were not heavy enough to balance the sash correctly. Fortunately, we found the "Add On Weight", available from SRS Hardware, which was spectifically designed for this situation. Check out the details at SRS Hardware if you find yourself in this same situation. #compasscarpentry #windowrepair #historicpreservation #oldhouselove #restoration #srshardware SRS Hardware

    Posted by Compass Carpentry on Thursday, August 30, 2018

    3 reviews for Add-on Cast Iron Sash Weights

    1. Chris C

      Encountered a situation where the pocket doors were too small to remove the weights, but the original weights were too light for the sash. These AOWs were a quick and easy solution to the problem. Their convenient design made it so that I could clip them right onto the sash cord without untying anything or removing the pulley; fantastic product!

    2. David C.

      Talk about convenience and ease of assembly! There’s a reason these sash weights are made to certain specifications…it’s to make your life easier, finish your jobs faster and minimize your last minute adjustments, resulting in a better adjusted well balanced sash. This is the result of a company being owned and operated by an actual career sash maker. I think it’s pretty cool being able to get stuff from a supplier who actually knows what they sell.

    3. iconicwindows

      I keep a pack of these weights in my truck at all times. Sometimes existing weights are just slightly off and these are the perfect fix. The problem with other add-on weights is that they are often square and don’t fit properly in some pockets. In addition, you need to disconnect the existing weight to add them on top. These guys here fit inside every pocket I have encountered and I do not have to disconnect the existing weight to add it. So tweaking during an install is quick and painless. I highly recommend you order some now. The day you realize that you need them you will be so very glad you have them. Nobody but SRS carries a product like this.

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    Presentation Sheet

    SRS Hardware Add On Weights Presentation Sheet

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    Technical Sheet

    SRS Hardware Add On Weights Technical Sheet

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    "Hi Justin,

    I received the first shipment yesterday and just wanted to let you know what a great product you've got!
    I used to work as a manufacturing engineer for Apple where I did lots of cosmetically-sensitive machining and surface finishing and I'm really impressed with both the design and execution of these parts. The cast surfaces are clean, the machined ones are burr-free, and the brushed ones aren't washed out from excessive polishing before texturing. The bearings in the pulley feel great and the action on the sash lock is nice and crispy.
    I'm happy to have hardware like this in my home! I know that products like this take a lot of effort so I wanted to acknowledge it.
    Henry W.
    Photo courtesy of Wood Window Rescue

    -PBB 225 ball bearing pulley and SL 01 sash lock
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