will this fit my Dremel 3000 rotary drill?

YES, collet nuts are the same size for all Dremels and other brand rotary tools such as Milwaukee.

Can this be used on the Dmel 7300

I am not sure, but I think so. The product description states the ones it does not work with, and the 7300 is not on that list. It fits my Black and Decker, and the various colletts allow for me to use just about any accessory made for any rotary tool, and also twist drill bits. I hope this helps

Will these work in the 4200 with the "EZ Change" system?

I own a basic 2 speed dremel so I can't answer with 100% assurance but my guess is NO. At the very least, the collet "nut" that is supplied will not work on your unit (is in fact replaced by the EZ change system). Also, the dremel website says the EZ402 mandrel is for use with "...exclusive EZ lock accessories.".

ASIN	B0000302Z6
Best Sellers Rank	24,902 in DIY & Tools ( See Top 100 in DIY & Tools ) 2,151 in Power Tool Accessories
Brand	Dremel
Capacity	0.13 inches
Compatible Devices	Drilling Machine
Compatible devices	Drilling Machine
Country of Origin	Mexico
Customer Reviews	4.7 out of 5 stars 6,764 Reviews
Global Trade Identification Number	00080596000196
Handle Type	Hand-tightened
Item Diameter	0.13 Inches
Item Weight	9 g
Item diameter	0.13 Inches
Item weight	9 g
Lock Type	Manual
Manufacturer	Dremel Mfg Co
Material	Metal
Thread Size	1/4-20 UNC
Thread size	1/4-20 UNC
UPC	080596000196
Unit Count	1.0 count

4485 Quick Change Collet Nut

Details

Description

Specifications

Reviews

Common Questions