---
title: Josam 21500 Roof Drain Engineering Specifications
description: Find engineering specification and product diagrams for Josam 21500 commercial roof drains, and all available product options.
---

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# Josam 21500 Roof Drain Engineering Specifications

Find engineering specifications and product diagrams for Josam 21500 15 in. roof drain, and all available product options. 

| [**Josam 21500 15-in. Roof Drain**](http://hy-techroof.com/manufacturers/josam) |  |  |
| --- | --- | --- |
| [Adjustable Extension Threaded (-AE)](http://hy-techroof.com/manufacturers/josam) | [Adjustable Extension with Threaded Rods (-AER)](https://resources.hy-techroof.com/josam-21500-aer-large-sump-with-adj-ext-using-threaded-rods) | [Internal Waterguard (-16)](http://hy-techroof.com/manufacturers/josam) |
| [Perforated Stainless Steel Gravel Guard (-19)](https://resources.hy-techroof.com/josam-21500-19-large-sump-with-perforated-stainless-steel-gravel-guard) | [Perforated Stainless Steel Extension (IRMA)](http://hy-techroof.com/josam-underdeck-clamps-for-21500-series-roof-drain/) | [Wide Flange & Perforated Stainless Steel Extension (IRMA-6)](https://resources.hy-techroof.com/josam-21500-irma-6-large-sump-wide-flange-perforated-ss-extension) |

 

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