1 set of 3.  These bulbs will fit Deere’s A and B, AO, AR, BN, BNH, D SN#143800 & UP, H, R, 50, 520, 530, 60, 620, 630, 70 DIESEL, 720 DIESEL, 730 DIESEL, 80, 820 2 CYL, 830 2 CYL, Allis Oliver, Massey tractors. 

They do not work with 6 volt tractors. They work best with 12 volts but can go as low as 10 volts and as high as 16 volts.

These bulbs do not work with later model positive ground tractors. 
 But I do have a non-polarity bulb that works great with positive ground tractors. See this link, https://www.ebay.com/itm/163853638171

There are pictures of my Deere 318 to illustrate how bright they are.

Ships from a small business from the Central part of the United States the same or next shipping day via USPS * with free tracking. Buyer pays actual shipping cost. No overcharge. After the first set, all other sets ship at no additional cost.

* Note: First Class shipping is the most cost-effective delivery, however, it is not insured. If you need your bulbs asap or if you would like your item insured for loss or damage, please select Priority shipping.