Caldwell Series 300 Block & Tackle Balance – 22" Stamp 21-5 (23-26 lbs) | 5/8" Channel, Non-Tilt/Side-Load Window, Pre-Assembled w/ Guides, Galvanized Steel, Sold Individually, Res. & Commercial, DIY
*Price sourced from Amazon.com. Last updated 2026-07-22. Price and availability subject to change.
Bottom line: The Caldwell Series 300 Block & Tackle Balance – 22" Stamp 21-5 (23-26 lbs) | 5/8" Channel, Non-Tilt/Side-Load Window, Pre-Assembled w/ Guides, Galvanized Steel, Sold Individually, Res. & Commercial, DIY is a niche pick — read recent reviews before buying in the retro software & media category, priced around $9.94. Read recent reviews carefully before committing.
SpecPicks Verdict
SpecPicks classifies WRS Caldwell Series 300 Block & Tackle Balance – 22" Stamp 21-5… as a niche pick — read recent reviews before buying in the retro software & media category, based on our editorial and benchmark analysis and our ranking model that weights rating × review-volume × price-fit. WRS's positioning sits within the broader category mid-tier. Use the Compare tool to put it side-by-side with two or three close alternatives before clicking through to Amazon.
Common buyer scenarios for retro software & media of this kind: matching it to an existing build, replacing a failing part, or upgrading from a previous-generation equivalent. Check the spec table below against your current setup — particularly socket / form-factor / power-rating fields — and confirm compatibility on the Amazon listing before purchase. Prices, stock, and Prime eligibility update directly from Amazon's catalog and may have moved since this page was last verified.
Pros & Cons
Pros
- ✓ Backed by WRS's warranty and support channels
- ✓ Ships via Amazon with Prime eligibility and the standard returns policy
Cons
- ✗ Confirm socket / form-factor / power-rating compatibility against your build before ordering
- ✗ Price, stock, and Prime eligibility update from Amazon and may have changed since this page was last verified
Key Features
- ENGINEERED FOR NON-TILT WINDOWS – Designed for side-load, non-tilt window systems with a standard 5/8″ metal channel, commonly used in vinyl and aluminum single- or double-hung frames. This balance measures 22" inches in length and supports 23-26 lbs sashes. Each balance arrives pre-assembled with top and bottom guides attached, so installation is fast and frustration-free—no special tools required.
- AVAILABLE IN LENGTHS FROM 8″ TO 49″ (3 TO 44 LB RANGE) – The Series 300 fits nearly all non-tilt window sizes, from light residential sashes to heavy commercial frames. Covers a complete range of lengths and weight ratings for versatile use. Each balance is precision-tested for smooth, reliable performance and long-term durability. Sold individually; accessories and hardware not included. Contact WRS if your exact size isn’t listed.
- SMOOTH, SAFE & SECURE OPERATION – The Series 300’s precision pulley and spring system balances the sash to prevent slamming or sticking, keeping windows steady at any height. Designed for quiet, reliable performance in homes, schools, and offices where safety and ease of use matter every day.
- HEAVY-DUTY GALVANIZED STEEL CONSTRUCTION – Crafted from high-strength galvanized steel for long-term durability and corrosion resistance. Precision pulleys and springs maintain smooth lift through thousands of cycles, ensuring reliable performance for years of daily use. Built tough for pros yet simple enough for DIY installation.
- TRUSTED SINCE 1989 – WRS Window Repair Systems has over 30 years of experience supplying reliable, high-quality hardware. Trusted nationwide by homeowners, contractors, schools, and property managers for dependable repairs and long-lasting performance.
Full Specifications
| Size | 21-5 (23-26 lbs) |
|---|---|
| Brand | WRS |
| Color | Metal |
| Style | American |
| Weight | 44 lb |
| Part Number | 01-30021-5 |
| Batteries Required? | No |
| Included Components | Series 300 Block & Tackle Balance |
| Item Package Quantity | 1 |
Ready to buy?
WRS Caldwell Series 300 Block & Tackle Balance – 22" Stamp 21-5 (23-26 lbs) | 5/8" Channel, Non-Tilt/Side-Load Window, Pre-Assembled w/ Guides, Galvanized Steel, Sold Individually, Res. & Commercial, DIY is available on Amazon with Prime shipping and the full Amazon returns policy. SpecPicks earns a small commission on qualifying purchases — thank you for supporting independent review work.
*Price sourced from Amazon.com. Last updated 2026-07-22. Price and availability subject to change.
Related Retro Software & Media
More guides & deep dives from the SpecPicks archive
Browse all articles & guides →- Best 1440p Gaming GPUs in 2026
- RTX 4070 Super vs RX 7800 XT — Which to Buy in 2026
- How to Build a Windows 98 Retro PC in 2026
- Best Budget Gaming PC Build 2026 — ~$1,000 ($800 on Sale)
- The Complete Voodoo5 5500 AGP Driver Guide (2026 Edition)
- Best Retro Handhelds in 2026 — From $35 to $500
- Emulation Hardware in 2026: FPGA, Software, and Cart-Reader Ecosystems
More reviews from the SpecPicks archive
Browse all reviews →- Ryzen AI Max 400 'Gorgon Halo' 192GB vs RTX 3060 12GB for Local LLMs
- Ryzen 5 5600G vs Ryzen 7 5700X for a Budget Gaming PC
- How to run Llama 3.1 8B on NVIDIA GeForce RTX 5090
- Best SSD to Upgrade a PS4 Pro: Crucial BX500 vs Samsung 870 EVO Real-World Gains
- GLM-5.2's Long-Horizon Agent Mode: Running It Locally in 2026
- How to run DeepSeek-R1 32B on NVIDIA GeForce RTX 4090
- Best Gaming Webcam and Microphone Bundle for Streamers in 2026
- Best Budget SSD for Gaming and PC Upgrades in 2026
- Build a Pi Zero W Handheld Retro Emulator in 2026: Full Parts List and Setup
- Build a 2001 GeForce3 + Win98 SE Gaming Rig in 2026: Parts and Gotchas
- 8BitDo SN30 Pro on SNES Classic and Genesis Mini: Bluetooth Setup Guide
- Building a Period-Correct 2003 WinXP Gaming Rig with Sound Blaster Audigy and a Modern 8BitDo Controller
- Best Controller for Fighting Games on PC in 2026
- Transcend CF133 CompactFlash as a Win98 Boot Drive: Speed Tests, Compatibility, and the Adapter That…
- How to run DeepSeek-R1 32B on Arc B580
- Best SSD for Retro PC IDE-to-SATA Builds (Win98, WinXP) in 2026
- Ollama vs llama.cpp vs vLLM on the RTX 3060 12GB
- AI-Assisted Sound Card Driver Install on Vintage WinXP: How a Vision LLM Automates the Sound Blaster Audigy FX
- On-Device AI Keyboards: Can an RTX 3060 12GB Train the Model?
- How nVidia Killed 3dfx — and Why Voodoo Still Haunts Every GPU Launch
- Self-Hosted Home Assistant on a Raspberry Pi 4 8GB (2026 Build)
- The Best Retro Game Emulators for Mac in 2026
- Best Budget 4K Gaming Monitor 2026: SANSUI 27" vs KOORUI QD-Mini LED vs ASUS TUF
- RTX 5090 Prebuilt vs a $700 RTX 3060 Local-LLM Box: What Extra VRAM Actually Buys