Use Product Options Menu to Select Tapered Spindle: 
Left Side Spindles (as you face it): A-TM5 (current lathes- built in 2002 and later with 5/16" motor shafts) or A-TM3 (lathes older than 2002 with 1/4" motor shafts)

Right Side Spindles (as you face it): A-TM6 (current lathes- built in 2002 and later with 5/16" motor shafts) or A-TM4 (lathes older than 2002 with 1/4" motor shafts)

Current models of BL Lathes refers to models built in 2002 and later. These lathes have 5/16" motor shafts. Older models (including Nos. 1 & 5 High Speed Bench Grinders) have 1/4" motor shafts and were built before 2002. 

Use for left and right hand mounting of buffs and wheels up to 4" in diameter. Also for Spindle and Hub Adapters.