TFN, TFFN, THHN or THWN Wire

What is the difference between these types of wires, and why would I use one vs the other? These are all single conductor wire and the four letters for each are to indicate the approvals that these wires went through. The differences with these wires are quite subtle, but there are differences to consider depending on the application they will be used in.

TFN - Thermoplastic Fixture Wire Nylon - This is rated for use in fixtures and is a single conductor solid wire.

TFFN - Thermoplastic Flexible Fixture Nylon - This wire is more flexible than TFN, THHN or THWN and is used in fixtures and appliances where more flexibility is required. TFFN is only available in 16AWG-18AWG and is stranded to ensure this better flexibility.

THHN - Thermoplastic High Heat Resistant Nylon - This wire is available in solid and stranded variations and has more size options than TFN or TFFN. This wire also has better heat resistance capabilities than TFN or TFFN.

THWN - Thermoplastic Heat and Water Resistant - THHN wire with the THWN listed is also water resistant and can be used in dry and wet locations where if it is rated as THHN only it can only be used in dry locations.

Applicable Part numbers

TFN
541801 BK005-ND 541801 WH005-ND 541801 RD005-ND A541801A-100-ND A541801L-100-ND A541801Y-100-ND A541801G-100-ND A541801R-1000-ND A541801W-1000-ND A541801B-1000-ND 541801 BR005-ND 541801 SL005-ND 541801 VI005-ND 541801 BL002-ND 541801 YL002-ND 541801 BR002-ND 541801 OR002-ND 541801 SL002-ND 541801 VI002-ND 541801 BK002-ND 541801 RD002-ND 541801 WH002-ND 541801 GR002-ND 541801 BL001-ND 541801 BR001-ND 541801 OR001-ND 541801 SL001-ND 541801 VI001-ND 541801 YL001-ND 541801 GR001-ND 541801 BK005 541801 WH005 541801 RD005 541801 OR005 541801 BL005 541801 YL005 541801 GR005 541801 RD001 541801 WH001 541801 BK001 541801 BR005 541801 SL005 541801 VI005 541801 BL002 541801 YL002 541801 BR002 541801 OR002 541801 SL002 541801 VI002 541801 BK002 541801 RD002 541801 WH002 541801 GR002 541801 BL001 541801 BR001 541801 OR001 541801 SL001 541801 VI001 541801 YL001 541801 GR001

TFFN
A541816B-100-ND A541816R-100-ND A541816W-100-ND A541816Y-100-ND A541816L-100-ND A541816G-100-ND 541816 BR005-ND 541816 OR005-ND 541816 VI005-ND 541626 BL005-ND 541626 BR005-ND 541626 SL005-ND 541626 VI005-ND 541626 OR005-ND 541626 BK005-ND 541626 GR005-ND 541626 RD005-ND 541626 YL005-ND 541626 WH005-ND 541816 BL002-ND 541816 BR002-ND 541816 OR002-ND 541816 VI002-ND 541816 YL002-ND 541816 BK002-ND 541816 GR002-ND 541816 RD002-ND 541816 WH002-ND 541626 BL002-ND 541626 BR002-ND 541626 OR002-ND 541626 VI002-ND 541626 SL002-ND 541626 BK002-ND 541626 GR002-ND 541626 RD002-ND 541626 WH002-ND 541626 YL002-ND 541816 BR001-ND 541816 OR001-ND 541816 SL001-ND 541816 VI001-ND 541816 YL001-ND 541626 OR001-ND 541626 VI001-ND 541626 BL001-ND 541626 BR001-ND 541626 SL001-ND 541816 BK001-ND 541816 GR001-ND 541816 RD001-ND 541816 WH001-ND 541626 GR001-ND 541626 WH001-ND 541626 BK001-ND 541626 RD001-ND 541626 YL001-ND 541626 RD003-ND 541816 BK003-ND 541816 BL001-ND 541816 BL003-ND 541816 BL013-ND 541816 BR003-ND 541816 GR003-ND 541816 GY001-ND 541816 PK002-ND 541816 RD003-ND 541816 SL005-ND 541816 SL002-ND 541816 WH003-ND 541816 YL003-ND 541816 BK005 541816 RD005 541816 WH005 541816 YL005 541816 BL005 541816 GR005 541816 BR005 541816 OR005 541816 VI005 541626 BL005 541626 BR005 541626 SL005 541626 VI005 541626 OR005 541626 BK005 541626 GR005 541626 RD005 541626 YL005 541626 WH005 541816 BL002 541816 BR002 541816 OR002 541816 VI002 541816 YL002 541816 BK002 541816 GR002 541816 RD002 541816 WH002 541626 BL002 541626 BR002 541626 OR002 541626 VI002 541626 SL002 541626 BK002 541626 GR002 541626 RD002 541626 WH002 541626 YL002 541816 BR001 541816 OR001 541816 SL001 541816 VI001 541816 YL001 541626 OR001 541626 VI001 541626 BL001 541626 BR001 541626 SL001 541816 BK001 541816 GR001 541816 RD001 541816 WH001 541626 GR001 541626 WH001 541626 BK001 541626 RD001 541626 YL001 541626 RD003 541816 BK003 541816 BL001 541816 BL003 541816 BL013 541816 BR003 541816 GR003 541816 GY001 541816 PK002 541816 RD003 541816 SL005 541816 SL002 541816 WH003 541816 YL003

THHN / THWN
A541401R-100-ND A541401B-100-ND A541419B-100-ND A541419G-100-ND A541419R-100-ND A541201B-100-ND A541019R-100-ND A541019B-100-ND A541401W-100-ND A541401Y-100-ND A541401G-100-ND A541419S-100-ND A541419L-100-ND A541419W-100-ND A541419V-100-ND A541419A-100-ND A541419Y-100-ND A541201W-100-ND A541201R-100-ND A541219R-100-ND A541219W-100-ND A541219B-100-ND A541219G-100-ND A541001W-100-ND A541401B-500-ND A541401R-500-ND A541401W-500-ND A541401G-500-ND A541401R-1000-ND A541401B-1000-ND A541401W-1000-ND A541419N-100-ND A541201G-100-ND A541019W-100-ND A541001B-100-ND A541001R-100-ND 541401 BL005-ND 541401 BR005-ND 541401 OR005-ND 541401 SL005-ND 541401 VI005-ND 541201 BL005-ND 541201 BR005-ND 541201 OR005-ND 541201 SL005-ND 541201 VI005-ND 541201 YL005-ND 541219 BL005-ND 541219 BR005-ND 541219 OR005-ND 541219 VI005-ND 541219 SL005-ND 541219 YL005-ND 541019 BR005-ND 541019 OR005-ND 541019 SL005-ND 541019 VI005-ND 541019 YL005-ND 541001 GR005-ND 541001 BR005-ND 541001 OR005-ND 541001 SL005-ND 541001 VI005-ND 541001 YL005-ND 541019 GR005-ND 541401 BL002-ND 541401 BR002-ND 541401 OR002-ND 541401 SL002-ND 541401 VI002-ND 541401 YL002-ND 541001 BL005-ND 541419 BL002-ND 541419 BR002-ND 541419 GY002-ND 541419 OR002-ND 541419 SL002-ND 541419 VI002-ND 541419 YL002-ND 540819 BK005-ND 540819 BR005-ND 540819 OR005-ND 540819 RD005-ND 540819 WH005-ND 540819 BL005-ND 540819 GR005-ND 540819 SL005-ND 540819 VI005-ND 540819 YL005-ND 540619 BK005-ND 540619 BL005-ND 540619 BR005-ND 540619 GR005-ND 540619 OR005-ND 540619 RD005-ND 540619 SL005-ND 540619 VI005-ND 540619 WH005-ND 540619 YL005-ND 541219 BL002-ND 541219 BR002-ND 541219 VI002-ND 541219 OR002-ND 541219 SL002-ND 541219 YL002-ND 541419 BK002-ND 541419 GR002-ND 541419 RD002-ND 541419 WH002-ND 541201 BL002-ND 541201 BR002-ND 541201 OR002-ND 541201 SL002-ND 541201 VI002-ND 541201 YL002-ND 541219 BK002-ND 541219 GR002-ND 541219 RD002-ND 541219 WH002-ND 541401 BL001-ND 541401 BR001-ND 541401 OR001-ND 541401 SL001-ND 541401 VI001-ND 541401 YL001-ND 541201 BK002-ND 541201 GR002-ND 541201 WH002-ND 541201 RD002-ND 541419 BL001-ND 541419 BR001-ND 541419 OR001-ND 541419 SL001-ND 541419 VI001-ND 541419 YL001-ND 541401 GR001-ND 541019 BL002-ND 541019 BR002-ND 541019 OR002-ND 541019 SL002-ND 541019 VI002-ND 541019 YL002-ND 540419 GR005-ND 540419 RD005-ND 540419 BK005-ND 540419 BL005-ND 540419 BR005-ND 540419 OR005-ND 540419 SL005-ND 540419 VI005-ND 540419 WH005-ND 540419 YL005-ND 541419 BK001-ND 541419 GR001-ND 541419 RD001-ND 541419 WH001-ND 541001 BR002-ND 541001 GR002-ND 541001 OR002-ND 541001 SL002-ND 541001 VI002-ND 541001 YL002-ND 541201 BL001-ND 541201 BR001-ND 541201 OR001-ND 541201 SL001-ND 541201 VI001-ND 541201 YL001-ND 541219 BL001-ND 541219 BR001-ND 541219 OR001-ND 541219 SL001-ND 541219 VI001-ND 541219 YL001-ND 541019 BK002-ND 541019 GR002-ND 541019 RD002-ND 541019 WH002-ND 540219 BR005-ND 540219 GR005-ND 540219 OR005-ND 540219 RD005-ND 540219 SL005-ND 540219 VI005-ND 540219 WH005-ND 540219 YL005-ND 540219 BL005-ND 541201 BK001-ND 541201 GR001-ND 541201 RD001-ND 541201 WH001-ND 541001 BR001-ND 541001 GR001-ND 541001 OR001-ND 541001 SL001-ND 541001 VI001-ND 541001 YL001-ND 541219 BK001-ND 541219 GR001-ND 541219 RD001-ND 541219 WH001-ND 541001 WH002-ND 541001 BK002-ND 541001 BL002-ND 541001 RD002-ND 540219 BK005-ND 541001 WH001-ND 541001 BK001-ND 541001 BL001-ND 541001 RD001-ND 541019 BR001-ND 541019 YL001-ND 541019 BL001-ND 541019 OR001-ND 541019 SL001-ND 541019 VI001-ND 541019 BK001-ND 541019 GR001-ND 541019 WH001-ND 541019 RD001-ND 540819 BK002-ND 540819 GR002-ND 540819 RD002-ND 540819 WH002-ND 540819 BL002-ND 540819 BR002-ND 540819 OR002-ND 540819 SL002-ND 540819 VI002-ND 540819 YL002-ND 540619 BK002-ND 540619 BL002-ND 540619 BR002-ND 540619 GR002-ND 540619 OR002-ND 540619 RD002-ND 540619 SL002-ND 540619 VI002-ND 540619 WH002-ND 540619 YL002-ND 540419 BK002-ND 540419 RD002-ND 540419 WH002-ND 540419 BL002-ND 540419 BR002-ND 540419 GR002-ND 540419 OR002-ND 540419 SL002-ND 540419 VI002-ND 540419 YL002-ND 540819 BK001-ND 540819 BL001-ND 540819 BR001-ND 540819 GR001-ND 540819 OR001-ND 540819 RD001-ND 540819 SL001-ND 540819 VI001-ND 540819 WH001-ND 540819 YL001-ND 540619 BK001-ND 540619 BL001-ND 540619 BR001-ND 540619 GR001-ND 540619 OR001-ND 540619 RD001-ND 540619 SL001-ND 540619 VI001-ND 540619 WH001-ND 540619 YL001-ND 540219 BK002-ND 540219 BL002-ND 540219 BR002-ND 540219 GR002-ND 540219 OR002-ND 540219 RD002-ND 540219 SL002-ND 540219 VI002-ND 540219 WH002-ND 540219 YL002-ND 540419 BL001-ND 540419 BR001-ND 540419 GR001-ND 540419 OR001-ND 540419 RD001-ND 540419 SL001-ND 540419 VI001-ND 540419 WH001-ND 540419 YL001-ND 540419 BK001-ND 540219 BK001-ND 540219 BL001-ND 540219 BR001-ND 540219 GR001-ND 540219 OR001-ND 540219 RD001-ND 540219 SL001-ND 540219 VI001-ND 540219 WH001-ND 540219 YL001-ND 540001 BK005-ND 540001 BK002-ND 541219 GR010-ND 541419 OR010-ND A541019L-100-ND 541401 RD005 541401 BK005 541419 BK005 541419 GR005 541419 RD005 541201 BK005 541019 RD005 541019 BK005 541401 WH005 541401 YL005 541401 GR005 541419 SL005 541419 BL005 541419 WH005 541419 VI005 541419 OR005 541419 YL005 541201 WH005 541201 RD005 541219 RD005 541219 WH005 541219 BK005 541219 GR005 541001 WH005 541401 BK002 541401 RD002 541401 WH002 541401 GR002 541401 RD001 541401 BK001 541401 WH001 541419 BR005 541201 GR005 541019 WH005 541001 BK005 541001 RD005 541401 BL005 541401 BR005 541401 OR005 541401 SL005 541401 VI005 541201 BL005 541201 BR005 541201 OR005 541201 SL005 541201 VI005 541201 YL005 541219 BL005 541219 BR005 541219 OR005 541219 VI005 541219 SL005 541219 YL005 541019 BR005 541019 OR005 541019 SL005 541019 VI005 541019 YL005 541001 GR005 541001 BR005 541001 OR005 541001 SL005 541001 VI005 541001 YL005 541019 GR005 541401 BL002 541401 BR002 541401 OR002 541401 SL002 541401 VI002 541401 YL002 541001 BL005 541419 BL002 541419 BR002 541419 GY002 541419 OR002 541419 SL002 541419 VI002 541419 YL002 540819 BK005 540819 BR005 540819 OR005 540819 RD005 540819 WH005 540819 BL005 540819 GR005 540819 SL005 540819 VI005 540819 YL005 540619 BK005 540619 BL005 540619 BR005 540619 GR005 540619 OR005 540619 RD005 540619 SL005 540619 VI005 540619 WH005 540619 YL005 541219 BL002 541219 BR002 541219 VI002 541219 OR002 541219 SL002 541219 YL002 541419 BK002 541419 GR002 541419 RD002 541419 WH002 541201 BL002 541201 BR002 541201 OR002 541201 SL002 541201 VI002 541201 YL002 541219 BK002 541219 GR002 541219 RD002 541219 WH002 541401 BL001 541401 BR001 541401 OR001 541401 SL001 541401 VI001 541401 YL001 541201 BK002 541201 GR002 541201 WH002 541201 RD002 541419 BL001 541419 BR001 541419 OR001 541419 SL001 541419 VI001 541419 YL001 541401 GR001 541019 BL002 541019 BR002 541019 OR002 541019 SL002 541019 VI002 541019 YL002 540419 GR005 540419 RD005 540419 BK005 540419 BL005 540419 BR005 540419 OR005 540419 SL005 540419 VI005 540419 WH005 540419 YL005 541419 BK001 541419 GR001 541419 RD001 541419 WH001 541001 BR002 541001 GR002 541001 OR002 541001 SL002 541001 VI002 541001 YL002 541201 BL001 541201 BR001 541201 OR001 541201 SL001 541201 VI001 541201 YL001 541219 BL001 541219 BR001 541219 OR001 541219 SL001 541219 VI001 541219 YL001 541019 BK002 541019 GR002 541019 RD002 541019 WH002 540219 BR005 540219 GR005 540219 OR005 540219 RD005 540219 SL005 540219 VI005 540219 WH005 540219 YL005 540219 BL005 541201 BK001 541201 GR001 541201 RD001 541201 WH001 541001 BR001 541001 GR001 541001 OR001 541001 SL001 541001 VI001 541001 YL001 541219 BK001 541219 GR001 541219 RD001 541219 WH001 541001 WH002 541001 BK002 541001 BL002 541001 RD002 540219 BK005 541001 WH001 541001 BK001 541001 BL001 541001 RD001 541019 BR001 541019 YL001 541019 BL001 541019 OR001 541019 SL001 541019 VI001 541019 BK001 541019 GR001 541019 WH001 541019 RD001 540819 BK002 540819 GR002 540819 RD002 540819 WH002 540819 BL002 540819 BR002 540819 OR002 540819 SL002 540819 VI002 540819 YL002 540619 BK002 540619 BL002 540619 BR002 540619 GR002 540619 OR002 540619 RD002 540619 SL002 540619 VI002 540619 WH002 540619 YL002 540419 BK002 540419 RD002 540419 WH002 540419 BL002 540419 BR002 540419 GR002 540419 OR002 540419 SL002 540419 VI002 540419 YL002 540819 BK001 540819 BL001 540819 BR001 540819 GR001 540819 OR001 540819 RD001 540819 SL001 540819 VI001 540819 WH001 540819 YL001 540619 BK001 540619 BL001 540619 BR001 540619 GR001 540619 OR001 540619 RD001 540619 SL001 540619 VI001 540619 WH001 540619 YL001 540219 BK002 540219 BL002 540219 BR002 540219 GR002 540219 OR002 540219 RD002 540219 SL002 540219 VI002 540219 WH002 540219 YL002 540419 BL001 540419 BR001 540419 GR001 540419 OR001 540419 RD001 540419 SL001 540419 VI001 540419 WH001 540419 YL001 540419 BK001 540219 BK001 540219 BL001 540219 BR001 540219 GR001 540219 OR001 540219 RD001 540219 SL001 540219 VI001 540219 WH001 540219 YL001 540001 BK005 540001 BK002 541219 GR010 541419 OR010 541019 BL005