If you want to try the same ones from Grainger that was previously mentioned. You can order the exact same ones from Northerntool.com, for a lot less, 200 pair for $26.99. http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200259124_200259124
John deer plugs, 80 pair for $13.49, http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200342824_200342824
If you want the corded type, same style you currently using, they have them for $1.79 pair. http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200259074_200259074
Be safe.
John deer plugs, 80 pair for $13.49, http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200342824_200342824
If you want the corded type, same style you currently using, they have them for $1.79 pair. http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200259074_200259074
Be safe.